diff --git a/.bazelrc b/.bazelrc
index 6ccd56a..b4eafb1 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -13,10 +13,6 @@
 
 build --announce_rc
 
-# Workaround Bazel worker crash (remove after upgrading to 4.1.0)
-# https://github.com/bazelbuild/bazel/issues/13333
-build --experimental_worker_multiplex=false
-
 test --build_tests_only
 test --test_output=errors
 test --java_toolchain=//tools:error_prone_warnings_toolchain_java11
diff --git a/Documentation/dev-bazel.txt b/Documentation/dev-bazel.txt
index 61565f8..314223e 100644
--- a/Documentation/dev-bazel.txt
+++ b/Documentation/dev-bazel.txt
@@ -268,7 +268,15 @@
   bazel-bin/Documentation/searchfree.zip
 ----
 
-To build the executable WAR with the documentation included:
+To generate HTML files skipping the zip archiving:
+
+----
+  bazel build Documentation
+----
+
+And open `bazel-bin/Documentation/index.html`.
+
+To build the Gerrit executable WAR with the documentation included:
 
 ----
   bazel build withdocs
diff --git a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
index b05050d..1628375 100644
--- a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
@@ -1085,7 +1085,7 @@
       ProjectConfig config = projectConfigFactory.read(md);
       config.updateProject(p -> p.setBooleanConfig(BooleanProjectConfig.USE_SIGNED_OFF_BY, value));
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
   }
 
@@ -1094,7 +1094,7 @@
       ProjectConfig config = projectConfigFactory.read(md);
       config.updateProject(p -> p.setBooleanConfig(BooleanProjectConfig.REQUIRE_CHANGE_ID, value));
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
   }
 
@@ -1599,7 +1599,7 @@
       projectConfig.commit(metaDataUpdate);
       metaDataUpdate.close();
       metaDataUpdate = null;
-      projectCache.evict(projectConfig.getProject());
+      projectCache.evictAndReindex(projectConfig.getProject());
     }
 
     @Override
diff --git a/java/com/google/gerrit/acceptance/DisabledAccountIndex.java b/java/com/google/gerrit/acceptance/DisabledAccountIndex.java
index 271d15c..7bd0c73 100644
--- a/java/com/google/gerrit/acceptance/DisabledAccountIndex.java
+++ b/java/com/google/gerrit/acceptance/DisabledAccountIndex.java
@@ -45,6 +45,11 @@
   }
 
   @Override
+  public void insert(AccountState obj) {
+    throw new UnsupportedOperationException("AccountIndex is disabled");
+  }
+
+  @Override
   public void replace(AccountState obj) {
     throw new UnsupportedOperationException("AccountIndex is disabled");
   }
diff --git a/java/com/google/gerrit/acceptance/DisabledChangeIndex.java b/java/com/google/gerrit/acceptance/DisabledChangeIndex.java
index 34f72f5c..7671ad4 100644
--- a/java/com/google/gerrit/acceptance/DisabledChangeIndex.java
+++ b/java/com/google/gerrit/acceptance/DisabledChangeIndex.java
@@ -52,6 +52,11 @@
   }
 
   @Override
+  public void insert(ChangeData obj) {
+    throw new UnsupportedOperationException("ChangeIndex is disabled");
+  }
+
+  @Override
   public void replace(ChangeData obj) {
     throw new UnsupportedOperationException("ChangeIndex is disabled");
   }
diff --git a/java/com/google/gerrit/acceptance/DisabledProjectIndex.java b/java/com/google/gerrit/acceptance/DisabledProjectIndex.java
index ed119ff..2e3dd90 100644
--- a/java/com/google/gerrit/acceptance/DisabledProjectIndex.java
+++ b/java/com/google/gerrit/acceptance/DisabledProjectIndex.java
@@ -50,6 +50,11 @@
   }
 
   @Override
+  public void insert(ProjectData obj) {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+
+  @Override
   public void replace(ProjectData obj) {
     throw new UnsupportedOperationException("ProjectIndex is disabled");
   }
diff --git a/java/com/google/gerrit/acceptance/ProjectResetter.java b/java/com/google/gerrit/acceptance/ProjectResetter.java
index d885303..46f7496 100644
--- a/java/com/google/gerrit/acceptance/ProjectResetter.java
+++ b/java/com/google/gerrit/acceptance/ProjectResetter.java
@@ -307,7 +307,7 @@
         Sets.union(
             projectsWithConfigChanges(restoredRefsByProject),
             projectsWithConfigChanges(deletedRefsByProject))) {
-      projectCache.evict(project);
+      projectCache.evictAndReindex(project);
     }
   }
 
diff --git a/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java b/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java
index e943519..f7a0669 100644
--- a/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java
+++ b/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java
@@ -45,6 +45,11 @@
   }
 
   @Override
+  public void insert(ChangeData obj) {
+    // do nothing
+  }
+
+  @Override
   public void replace(ChangeData obj) {
     // do nothing
   }
diff --git a/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java b/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
index e7354ab..394f0f8 100644
--- a/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
+++ b/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
@@ -148,7 +148,7 @@
         setExclusiveGroupPermissions(projectConfig, projectUpdate.exclusiveGroupPermissions());
         projectConfig.commit(metaDataUpdate);
       }
-      projectCache.evict(nameKey);
+      projectCache.evictAndReindex(nameKey);
     }
 
     private void removePermissions(
@@ -293,7 +293,7 @@
 
         setConfig(projectConfig);
         try {
-          projectCache.evict(nameKey);
+          projectCache.evictAndReindex(nameKey);
         } catch (Exception e) {
           // Evicting the project from the cache, also triggers a reindex of the project.
           // The reindex step fails if the project config is invalid. That's fine, since it was our
@@ -311,7 +311,7 @@
         testProjectInvalidation.projectConfigUpdater().forEach(c -> c.accept(projectConfig));
         setConfig(projectConfig);
         try {
-          projectCache.evict(nameKey);
+          projectCache.evictAndReindex(nameKey);
         } catch (Exception e) {
           // Evicting the project from the cache, also triggers a reindex of the project.
           // The reindex step fails if the project config is invalid. That's fine, since it was our
diff --git a/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java b/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
index 44a377a..6ed1a51 100644
--- a/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
+++ b/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
@@ -178,6 +178,12 @@
   }
 
   @Override
+  public void insert(V obj) {
+    // TODO: Implement real insert() if it helps performance
+    replace(obj);
+  }
+
+  @Override
   public void deleteAll() {
     // Delete the index, if it exists.
     String endpoint = indexName + client.adapter().indicesExistParams();
diff --git a/java/com/google/gerrit/index/Index.java b/java/com/google/gerrit/index/Index.java
index 44f8b42..e662bc8 100644
--- a/java/com/google/gerrit/index/Index.java
+++ b/java/com/google/gerrit/index/Index.java
@@ -40,6 +40,16 @@
   void close();
 
   /**
+   * Insert a document into the index.
+   *
+   * <p>Results may not be immediately visible to searchers, but should be visible within a
+   * reasonable amount of time.
+   *
+   * @param obj document object
+   */
+  void insert(V obj);
+
+  /**
    * Update a document in the index.
    *
    * <p>Semantically equivalent to deleting the document and reinserting it with new field values. A
diff --git a/java/com/google/gerrit/lucene/ChangeSubIndex.java b/java/com/google/gerrit/lucene/ChangeSubIndex.java
index 36f800f..475dac4 100644
--- a/java/com/google/gerrit/lucene/ChangeSubIndex.java
+++ b/java/com/google/gerrit/lucene/ChangeSubIndex.java
@@ -90,6 +90,11 @@
   }
 
   @Override
+  public void insert(ChangeData obj) {
+    throw new UnsupportedOperationException("don't use ChangeSubIndex directly");
+  }
+
+  @Override
   public void replace(ChangeData obj) {
     throw new UnsupportedOperationException("don't use ChangeSubIndex directly");
   }
diff --git a/java/com/google/gerrit/lucene/LuceneAccountIndex.java b/java/com/google/gerrit/lucene/LuceneAccountIndex.java
index 87b7cce..c4a5240 100644
--- a/java/com/google/gerrit/lucene/LuceneAccountIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneAccountIndex.java
@@ -144,6 +144,15 @@
   }
 
   @Override
+  public void insert(AccountState as) {
+    try {
+      insert(toDocument(as)).get();
+    } catch (ExecutionException | InterruptedException e) {
+      throw new StorageException(e);
+    }
+  }
+
+  @Override
   public void delete(Account.Id key) {
     try {
       delete(idTerm(getSchema().useLegacyNumericFields(), key)).get();
diff --git a/java/com/google/gerrit/lucene/LuceneChangeIndex.java b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
index 201c4a3..66fbda9 100644
--- a/java/com/google/gerrit/lucene/LuceneChangeIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
@@ -291,6 +291,23 @@
   }
 
   @Override
+  public void insert(ChangeData cd) {
+    Term id = LuceneChangeIndex.idTerm(idTerm, idField, cd);
+    // toDocument is essentially static and doesn't depend on the specific
+    // sub-index, so just pick one.
+    Document doc = openIndex.toDocument(cd);
+    try {
+      if (cd.change().isNew()) {
+        openIndex.insert(doc).get();
+      } else {
+        closedIndex.insert(doc).get();
+      }
+    } catch (ExecutionException | InterruptedException e) {
+      throw new StorageException(e);
+    }
+  }
+
+  @Override
   public void delete(Change.Id changeId) {
     Term id = LuceneChangeIndex.idTerm(idTerm, idField, changeId);
     try {
diff --git a/java/com/google/gerrit/lucene/LuceneGroupIndex.java b/java/com/google/gerrit/lucene/LuceneGroupIndex.java
index 816739b..f7a2248 100644
--- a/java/com/google/gerrit/lucene/LuceneGroupIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneGroupIndex.java
@@ -125,6 +125,15 @@
   }
 
   @Override
+  public void insert(InternalGroup group) {
+    try {
+      insert(toDocument(group)).get();
+    } catch (ExecutionException | InterruptedException e) {
+      throw new StorageException(e);
+    }
+  }
+
+  @Override
   public void delete(AccountGroup.UUID key) {
     try {
       delete(idTerm(key)).get();
diff --git a/java/com/google/gerrit/lucene/LuceneProjectIndex.java b/java/com/google/gerrit/lucene/LuceneProjectIndex.java
index 7e7aecb..11707be 100644
--- a/java/com/google/gerrit/lucene/LuceneProjectIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneProjectIndex.java
@@ -125,6 +125,15 @@
   }
 
   @Override
+  public void insert(ProjectData projectState) {
+    try {
+      insert(toDocument(projectState)).get();
+    } catch (ExecutionException | InterruptedException e) {
+      throw new StorageException(e);
+    }
+  }
+
+  @Override
   public void delete(Project.NameKey nameKey) {
     try {
       delete(idTerm(nameKey)).get();
diff --git a/java/com/google/gerrit/pgm/Reindex.java b/java/com/google/gerrit/pgm/Reindex.java
index 0872340..9f2e7a7 100644
--- a/java/com/google/gerrit/pgm/Reindex.java
+++ b/java/com/google/gerrit/pgm/Reindex.java
@@ -17,10 +17,12 @@
 import static java.util.Objects.requireNonNull;
 import static java.util.stream.Collectors.toSet;
 
+import com.google.common.cache.Cache;
 import com.google.common.collect.Sets;
 import com.google.gerrit.common.Die;
 import com.google.gerrit.elasticsearch.ElasticIndexModule;
 import com.google.gerrit.extensions.config.FactoryModule;
+import com.google.gerrit.extensions.registration.DynamicMap;
 import com.google.gerrit.index.Index;
 import com.google.gerrit.index.IndexDefinition;
 import com.google.gerrit.index.IndexType;
@@ -29,17 +31,24 @@
 import com.google.gerrit.lucene.LuceneIndexModule;
 import com.google.gerrit.pgm.util.BatchProgramModule;
 import com.google.gerrit.pgm.util.SiteProgram;
+import com.google.gerrit.server.cache.CacheDisplay;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.index.IndexModule;
 import com.google.gerrit.server.index.change.ChangeSchemaDefinitions;
 import com.google.gerrit.server.index.options.AutoFlush;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.gerrit.server.plugins.PluginGuiceEnvironment;
 import com.google.gerrit.server.util.ReplicaUtil;
+import com.google.inject.AbstractModule;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.google.inject.Key;
 import com.google.inject.Module;
+import com.google.inject.multibindings.OptionalBinder;
+import java.io.StringWriter;
+import java.io.Writer;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -48,6 +57,8 @@
 import java.util.Set;
 import java.util.TreeSet;
 import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.util.io.NullOutputStream;
 import org.kohsuke.args4j.Option;
@@ -78,6 +89,7 @@
   private Config globalConfig;
 
   @Inject private Collection<IndexDefinition<?, ?, ?>> indexDefs;
+  @Inject private DynamicMap<Cache<?, ?>> cacheMap;
 
   @Override
   public int run() throws Exception {
@@ -163,6 +175,16 @@
       throw new IllegalStateException("unsupported index.type = " + indexType);
     }
     modules.add(indexModule);
+    modules.add(
+        new AbstractModule() {
+          @Override
+          protected void configure() {
+            super.configure();
+            OptionalBinder.newOptionalBinder(binder(), IsFirstInsertForEntry.class)
+                .setBinding()
+                .toInstance(IsFirstInsertForEntry.YES);
+          }
+        });
     modules.add(new BatchProgramModule(dbInjector));
     modules.add(
         new FactoryModule() {
@@ -210,6 +232,20 @@
     System.out.format(
         "Index %s in version %d is %sready\n",
         def.getName(), index.getSchema().getVersion(), result.success() ? "" : "NOT ");
+
+    try (Writer sw = new StringWriter()) {
+      sw.write(String.format("Cache Statistics at the end of reindexing %s\n", def.getName()));
+      new CacheDisplay(
+              sw,
+              StreamSupport.stream(cacheMap.spliterator(), false)
+                  .map(e -> new CacheInfo(e.getExportName(), e.get()))
+                  .collect(Collectors.toList()))
+          .displayCaches();
+      System.out.print(sw.toString());
+    } catch (Exception e) {
+      System.out.format("Error displaying the cache statistics\n" + e.getMessage());
+    }
+
     return result.success();
   }
 }
diff --git a/java/com/google/gerrit/pgm/util/BatchProgramModule.java b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
index 508f96c..71aec5b 100644
--- a/java/com/google/gerrit/pgm/util/BatchProgramModule.java
+++ b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
@@ -126,7 +126,7 @@
     // We're just running through each change
     // once, so don't worry about cache removal.
     bind(new TypeLiteral<DynamicSet<CacheRemovalListener>>() {}).toInstance(DynamicSet.emptySet());
-    bind(new TypeLiteral<DynamicMap<Cache<?, ?>>>() {}).toInstance(DynamicMap.emptyMap());
+    DynamicMap.mapOf(binder(), new TypeLiteral<Cache<?, ?>>() {});
     bind(new TypeLiteral<List<CommentLinkInfo>>() {})
         .toProvider(CommentLinkProvider.class)
         .in(SINGLETON);
diff --git a/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java b/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
index 6c76de7..60f3d4b 100644
--- a/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
+++ b/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
@@ -121,7 +121,7 @@
           });
 
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
   }
 
diff --git a/java/com/google/gerrit/server/cache/CacheDisplay.java b/java/com/google/gerrit/server/cache/CacheDisplay.java
new file mode 100644
index 0000000..60f5186
--- /dev/null
+++ b/java/com/google/gerrit/server/cache/CacheDisplay.java
@@ -0,0 +1,129 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.cache;
+
+import com.google.common.base.Strings;
+import java.io.IOException;
+import java.io.Writer;
+import java.util.Collection;
+
+public class CacheDisplay {
+
+  private final Writer stdout;
+  private final int nw;
+  private final Collection<CacheInfo> caches;
+
+  public CacheDisplay(Writer stdout, int nw, Collection<CacheInfo> caches) {
+    this.stdout = stdout;
+    this.nw = nw;
+    this.caches = caches;
+  }
+
+  public CacheDisplay(Writer stdout, Collection<CacheInfo> caches) {
+    this(stdout, 30, caches);
+  }
+
+  public void displayCaches() throws IOException {
+    stdout.write(
+        String.format( //
+            "%1s %-" + nw + "s|%-21s|  %-5s |%-9s|\n" //
+            ,
+            "" //
+            ,
+            "Name" //
+            ,
+            "Entries" //
+            ,
+            "AvgGet" //
+            ,
+            "Hit Ratio" //
+            ));
+    stdout.write(
+        String.format( //
+            "%1s %-" + nw + "s|%6s %6s %7s|  %-5s  |%-4s %-4s|\n" //
+            ,
+            "" //
+            ,
+            "" //
+            ,
+            "Mem" //
+            ,
+            "Disk" //
+            ,
+            "Space" //
+            ,
+            "" //
+            ,
+            "Mem" //
+            ,
+            "Disk" //
+            ));
+    stdout.write("--");
+    for (int i = 0; i < nw; i++) {
+      stdout.write('-');
+    }
+    stdout.write("+---------------------+---------+---------+\n");
+    printMemoryCoreCaches(caches);
+    printMemoryPluginCaches(caches);
+    printDiskCaches(caches);
+    stdout.write('\n');
+  }
+
+  private void printMemoryCoreCaches(Collection<CacheInfo> caches) throws IOException {
+    for (CacheInfo cache : caches) {
+      if (!cache.name.contains("-") && CacheInfo.CacheType.MEM.equals(cache.type)) {
+        printCache(cache);
+      }
+    }
+  }
+
+  private void printMemoryPluginCaches(Collection<CacheInfo> caches) throws IOException {
+    for (CacheInfo cache : caches) {
+      if (cache.name.contains("-") && CacheInfo.CacheType.MEM.equals(cache.type)) {
+        printCache(cache);
+      }
+    }
+  }
+
+  private void printDiskCaches(Collection<CacheInfo> caches) throws IOException {
+    for (CacheInfo cache : caches) {
+      if (CacheInfo.CacheType.DISK.equals(cache.type)) {
+        printCache(cache);
+      }
+    }
+  }
+
+  private void printCache(CacheInfo cache) throws IOException {
+    stdout.write(
+        String.format(
+            "%1s %-" + nw + "s|%6s %6s %7s| %7s |%4s %4s|\n",
+            CacheInfo.CacheType.DISK.equals(cache.type) ? "D" : "",
+            cache.name,
+            nullToEmpty(cache.entries.mem),
+            nullToEmpty(cache.entries.disk),
+            Strings.nullToEmpty(cache.entries.space),
+            Strings.nullToEmpty(cache.averageGet),
+            formatAsPercent(cache.hitRatio.mem),
+            formatAsPercent(cache.hitRatio.disk)));
+  }
+
+  private static String nullToEmpty(Long l) {
+    return l != null ? String.valueOf(l) : "";
+  }
+
+  private static String formatAsPercent(Integer i) {
+    return i != null ? i + "%" : "";
+  }
+}
diff --git a/java/com/google/gerrit/server/cache/CacheInfo.java b/java/com/google/gerrit/server/cache/CacheInfo.java
new file mode 100644
index 0000000..d6eb065
--- /dev/null
+++ b/java/com/google/gerrit/server/cache/CacheInfo.java
@@ -0,0 +1,133 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.cache;
+
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheStats;
+
+public class CacheInfo {
+
+  public String name;
+  public CacheType type;
+  public EntriesInfo entries;
+  public String averageGet;
+  public HitRatioInfo hitRatio;
+
+  public CacheInfo(Cache<?, ?> cache) {
+    this(null, cache);
+  }
+
+  public CacheInfo(String name, Cache<?, ?> cache) {
+    this.name = name;
+
+    CacheStats stat = cache.stats();
+
+    entries = new EntriesInfo();
+    entries.setMem(cache.size());
+
+    averageGet = duration(stat.averageLoadPenalty());
+
+    hitRatio = new HitRatioInfo();
+    hitRatio.setMem(stat.hitCount(), stat.requestCount());
+
+    if (cache instanceof PersistentCache) {
+      type = CacheType.DISK;
+      PersistentCache.DiskStats diskStats = ((PersistentCache) cache).diskStats();
+      entries.setDisk(diskStats.size());
+      entries.setSpace(diskStats.space());
+      hitRatio.setDisk(diskStats.hitCount(), diskStats.requestCount());
+    } else {
+      type = CacheType.MEM;
+    }
+  }
+
+  private static String duration(double ns) {
+    if (ns < 0.5) {
+      return null;
+    }
+    String suffix = "ns";
+    if (ns >= 1000.0) {
+      ns /= 1000.0;
+      suffix = "us";
+    }
+    if (ns >= 1000.0) {
+      ns /= 1000.0;
+      suffix = "ms";
+    }
+    if (ns >= 1000.0) {
+      ns /= 1000.0;
+      suffix = "s";
+    }
+    return String.format("%4.1f%s", ns, suffix).trim();
+  }
+
+  public static class EntriesInfo {
+    public Long mem;
+    public Long disk;
+    public String space;
+
+    public void setMem(long mem) {
+      this.mem = mem != 0 ? mem : null;
+    }
+
+    public void setDisk(long disk) {
+      this.disk = disk != 0 ? disk : null;
+    }
+
+    public void setSpace(double value) {
+      space = bytes(value);
+    }
+
+    private static String bytes(double value) {
+      value /= 1024;
+      String suffix = "k";
+
+      if (value > 1024) {
+        value /= 1024;
+        suffix = "m";
+      }
+      if (value > 1024) {
+        value /= 1024;
+        suffix = "g";
+      }
+      return String.format("%1$6.2f%2$s", value, suffix).trim();
+    }
+  }
+
+  public static class HitRatioInfo {
+    public Integer mem;
+    public Integer disk;
+
+    public void setMem(long value, long total) {
+      mem = percent(value, total);
+    }
+
+    public void setDisk(long value, long total) {
+      disk = percent(value, total);
+    }
+
+    private static Integer percent(long value, long total) {
+      if (total <= 0) {
+        return null;
+      }
+      return (int) ((100 * value) / total);
+    }
+  }
+
+  public enum CacheType {
+    MEM,
+    DISK
+  }
+}
diff --git a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
index 1006c23..cca8681 100644
--- a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
+++ b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
@@ -3151,7 +3151,7 @@
       }
       if (isConfig(cmd)) {
         logger.atFine().log("Reloading project in cache");
-        projectCache.evict(project);
+        projectCache.evictAndReindex(project);
         ProjectState ps =
             projectCache.get(project.getNameKey()).orElseThrow(illegalState(project.getNameKey()));
         try {
diff --git a/java/com/google/gerrit/server/group/db/RenameGroupOp.java b/java/com/google/gerrit/server/group/db/RenameGroupOp.java
index 843b346..257bc16 100644
--- a/java/com/google/gerrit/server/group/db/RenameGroupOp.java
+++ b/java/com/google/gerrit/server/group/db/RenameGroupOp.java
@@ -123,7 +123,7 @@
       //
       GroupReference ref = config.getGroup(uuid);
       if (ref == null || newName.equals(ref.getName())) {
-        projectCache.evict(config.getProject());
+        projectCache.evictAndReindex(config.getProject());
         return;
       }
 
@@ -132,7 +132,7 @@
       md.setMessage("Rename group " + oldName + " to " + newName + "\n");
       try {
         config.commit(md);
-        projectCache.evict(config.getProject());
+        projectCache.evictAndReindex(config.getProject());
         success = true;
       } catch (IOException e) {
         logger.atSevere().withCause(e).log(
diff --git a/java/com/google/gerrit/server/index/IndexModule.java b/java/com/google/gerrit/server/index/IndexModule.java
index 17665c0..8b04c8d 100644
--- a/java/com/google/gerrit/server/index/IndexModule.java
+++ b/java/com/google/gerrit/server/index/IndexModule.java
@@ -51,6 +51,7 @@
 import com.google.gerrit.server.index.group.GroupIndexer;
 import com.google.gerrit.server.index.group.GroupIndexerImpl;
 import com.google.gerrit.server.index.group.GroupSchemaDefinitions;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.gerrit.server.index.project.ProjectIndexDefinition;
 import com.google.gerrit.server.index.project.ProjectIndexerImpl;
 import com.google.inject.Inject;
@@ -59,6 +60,7 @@
 import com.google.inject.Provides;
 import com.google.inject.ProvisionException;
 import com.google.inject.Singleton;
+import com.google.inject.multibindings.OptionalBinder;
 import java.util.Collection;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
@@ -143,6 +145,9 @@
     }
 
     DynamicSet.setOf(binder(), OnlineUpgradeListener.class);
+    OptionalBinder.newOptionalBinder(binder(), IsFirstInsertForEntry.class)
+        .setDefault()
+        .toInstance(IsFirstInsertForEntry.NO);
   }
 
   @Provides
diff --git a/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java b/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
index 63889b7..ec27db0 100644
--- a/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
+++ b/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
@@ -27,6 +27,7 @@
 import com.google.gerrit.server.account.AccountState;
 import com.google.gerrit.server.account.Accounts;
 import com.google.gerrit.server.index.IndexExecutor;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
@@ -50,15 +51,18 @@
   private final ListeningExecutorService executor;
   private final Accounts accounts;
   private final AccountCache accountCache;
+  private final IsFirstInsertForEntry isFirstInsertForEntry;
 
   @Inject
   AllAccountsIndexer(
       @IndexExecutor(BATCH) ListeningExecutorService executor,
       Accounts accounts,
-      AccountCache accountCache) {
+      AccountCache accountCache,
+      IsFirstInsertForEntry isFirstInsertForEntry) {
     this.executor = executor;
     this.accounts = accounts;
     this.accountCache = accountCache;
+    this.isFirstInsertForEntry = isFirstInsertForEntry;
   }
 
   @Override
@@ -92,7 +96,11 @@
                 try {
                   Optional<AccountState> a = accountCache.get(id);
                   if (a.isPresent()) {
-                    index.replace(a.get());
+                    if (isFirstInsertForEntry.equals(isFirstInsertForEntry.YES)) {
+                      index.insert(a.get());
+                    } else {
+                      index.replace(a.get());
+                    }
                   } else {
                     index.delete(id);
                   }
diff --git a/java/com/google/gerrit/server/index/change/AllChangesIndexer.java b/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
index ab42e5a..30205b6 100644
--- a/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
+++ b/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
@@ -20,15 +20,16 @@
 import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
 import static com.google.gerrit.server.git.QueueProvider.QueueType.BATCH;
 
+import com.google.auto.value.AutoValue;
 import com.google.common.base.Stopwatch;
+import com.google.common.collect.Sets;
 import com.google.common.flogger.FluentLogger;
-import com.google.common.primitives.Ints;
+import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.ListeningExecutorService;
 import com.google.common.util.concurrent.UncheckedExecutionException;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.Project;
-import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.index.SiteIndexer;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.git.MultiProgressMonitor;
@@ -37,6 +38,7 @@
 import com.google.gerrit.server.index.OnlineReindexMode;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.notedb.ChangeNotes.Factory.ChangeNotesResult;
+import com.google.gerrit.server.notedb.ChangeNotes.Factory.ScanResult;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.inject.Inject;
@@ -44,11 +46,13 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
-import java.util.Objects;
+import java.util.Set;
 import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.atomic.AtomicBoolean;
-import org.eclipse.jgit.errors.RepositoryNotFoundException;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.stream.Collectors;
 import org.eclipse.jgit.lib.ProgressMonitor;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.TextProgressMonitor;
@@ -62,6 +66,14 @@
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
   private static final int PROJECT_SLICE_MAX_REFS = 1000;
 
+  private static class ProjectsCollectionFailure extends Exception {
+    private static final long serialVersionUID = 1L;
+
+    public ProjectsCollectionFailure(String message) {
+      super(message);
+    }
+  }
+
   private final ChangeData.Factory changeDataFactory;
   private final GitRepositoryManager repoManager;
   private final ListeningExecutorService executor;
@@ -85,103 +97,58 @@
     this.projectCache = projectCache;
   }
 
-  private static class ProjectSlice {
-    private final Project.NameKey name;
-    private final int slice;
-    private final int slices;
+  @AutoValue
+  public abstract static class ProjectSlice {
+    public abstract Project.NameKey name();
 
-    ProjectSlice(Project.NameKey name, int slice, int slices) {
-      this.name = name;
-      this.slice = slice;
-      this.slices = slices;
-    }
+    public abstract int slice();
 
-    public Project.NameKey getName() {
-      return name;
-    }
+    public abstract int slices();
 
-    public int getSlice() {
-      return slice;
-    }
+    public abstract ScanResult scanResult();
 
-    public int getSlices() {
-      return slices;
+    private static ProjectSlice create(Project.NameKey name, int slice, int slices, ScanResult sr) {
+      return new AutoValue_AllChangesIndexer_ProjectSlice(name, slice, slices, sr);
     }
   }
 
   @Override
   public Result indexAll(ChangeIndex index) {
-    ProgressMonitor pm = new TextProgressMonitor();
-    pm.beginTask("Collecting projects", ProgressMonitor.UNKNOWN);
-    List<ProjectSlice> projectSlices = new ArrayList<>();
-    int changeCount = 0;
-    Stopwatch sw = Stopwatch.createStarted();
-    int projectsFailed = 0;
-    for (Project.NameKey name : projectCache.all()) {
-      try (Repository repo = repoManager.openRepository(name)) {
-        // The simplest approach to distribute indexing would be to let each thread grab a project
-        // and index it fully. But if a site has one big project and 100s of small projects, then
-        // in the beginning all CPUs would be busy reindexing projects. But soon enough all small
-        // projects have been reindexed, and only the thread that reindexes the big project is
-        // still working. The other threads would idle. Reindexing the big project on a single
-        // thread becomes the critical path. Bringing in more CPUs would not speed up things.
-        //
-        // To avoid such situations, we split big repos into smaller parts and let
-        // the thread pool index these smaller parts. This splitting introduces an overhead in the
-        // workload setup and there might be additional slow-downs from multiple threads
-        // concurrently working on different parts of the same project. But for Wikimedia's Gerrit,
-        // which had 2 big projects, many middle sized ones, and lots of smaller ones, the
-        // splitting of repos into smaller parts reduced indexing time from 1.5 hours to 55 minutes
-        // in 2020.
-        int size = estimateSize(repo);
-        if (size == 0) {
-          pm.update(1);
-          continue;
-        }
-        changeCount += size;
-        int slices = 1 + size / PROJECT_SLICE_MAX_REFS;
-        if (slices > 1) {
-          verboseWriter.println("Submitting " + name + " for indexing in " + slices + " slices");
-        }
-        for (int slice = 0; slice < slices; slice++) {
-          projectSlices.add(new ProjectSlice(name, slice, slices));
-        }
-      } catch (IOException e) {
-        logger.atSevere().withCause(e).log("Error collecting project %s", name);
-        projectsFailed++;
-        if (projectsFailed > projectCache.all().size() / 2) {
-          logger.atSevere().log("Over 50%% of the projects could not be collected: aborted");
-          return Result.create(sw, false, 0, 0);
-        }
-      }
-      pm.update(1);
-    }
-    pm.endTask();
-    setTotalWork(changeCount);
+    // The simplest approach to distribute indexing would be to let each thread grab a project
+    // and index it fully. But if a site has one big project and 100s of small projects, then
+    // in the beginning all CPUs would be busy reindexing projects. But soon enough all small
+    // projects have been reindexed, and only the thread that reindexes the big project is
+    // still working. The other threads would idle. Reindexing the big project on a single
+    // thread becomes the critical path. Bringing in more CPUs would not speed up things.
+    //
+    // To avoid such situations, we split big repos into smaller parts and let
+    // the thread pool index these smaller parts. This splitting introduces an overhead in the
+    // workload setup and there might be additional slow-downs from multiple threads
+    // concurrently working on different parts of the same project. But for Wikimedia's Gerrit,
+    // which had 2 big projects, many middle sized ones, and lots of smaller ones, the
+    // splitting of repos into smaller parts reduced indexing time from 1.5 hours to 55 minutes
+    // in 2020.
 
-    // projectSlices are currently grouped by projects. First all slices for project1, followed
-    // by all slices for project2, and so on. As workers pick tasks sequentially, multiple threads
-    // would typically work concurrently on different slices of the same project. While this is not
-    // a big issue, shuffling the list beforehand helps with ungrouping the project slices, so
-    // different slices are less likely to be worked on concurrently.
+    Stopwatch sw = Stopwatch.createStarted();
+    List<ProjectSlice> projectSlices;
+    try {
+      projectSlices = new SliceCreator().create();
+    } catch (ProjectsCollectionFailure | InterruptedException | ExecutionException e) {
+      logger.atSevere().log(e.getMessage());
+      return Result.create(sw, false, 0, 0);
+    }
+
+    // Since project slices are created in parallel, they are somewhat shuffled already. However,
+    // the number of threads used to create the project slices doesn't guarantee good randomization.
+    // If the slices are not shuffled well, then multiple threads would typically work concurrently
+    // on different slices of the same project. While this is not a big issue, shuffling the list
+    // beforehand helps with ungrouping the project slices, so different slices are less likely to
+    // be worked on concurrently.
     // This shuffling gave a 6% runtime reduction for Wikimedia's Gerrit in 2020.
     Collections.shuffle(projectSlices);
     return indexAll(index, projectSlices);
   }
 
-  private int estimateSize(Repository repo) throws IOException {
-    // Estimate size based on IDs that show up in ref names. This is not perfect, since patch set
-    // refs may exist for changes whose metadata was never successfully stored. But that's ok, as
-    // the estimate is just used as a heuristic for sorting projects.
-    long size =
-        repo.getRefDatabase().getRefsByPrefix(RefNames.REFS_CHANGES).stream()
-            .map(r -> Change.Id.fromRef(r.getName()))
-            .filter(Objects::nonNull)
-            .distinct()
-            .count();
-    return Ints.saturatedCast(size);
-  }
-
   private SiteIndexer.Result indexAll(ChangeIndex index, List<ProjectSlice> projectSlices) {
     Stopwatch sw = Stopwatch.createStarted();
     MultiProgressMonitor mpm = new MultiProgressMonitor(progressOut, "Reindexing changes");
@@ -194,9 +161,9 @@
     AtomicBoolean ok = new AtomicBoolean(true);
 
     for (ProjectSlice projectSlice : projectSlices) {
-      Project.NameKey name = projectSlice.getName();
-      int slice = projectSlice.getSlice();
-      int slices = projectSlice.getSlices();
+      Project.NameKey name = projectSlice.name();
+      int slice = projectSlice.slice();
+      int slices = projectSlice.slices();
       ListenableFuture<?> future =
           executor.submit(
               reindexProject(
@@ -204,6 +171,7 @@
                   name,
                   slice,
                   slices,
+                  projectSlice.scanResult(),
                   doneTask,
                   failedTask));
       String description = "project " + name + " (" + slice + "/" + slices + ")";
@@ -244,7 +212,13 @@
 
   public Callable<Void> reindexProject(
       ChangeIndexer indexer, Project.NameKey project, Task done, Task failed) {
-    return reindexProject(indexer, project, 0, 1, done, failed);
+    try (Repository repo = repoManager.openRepository(project)) {
+      return reindexProject(
+          indexer, project, 0, 1, ChangeNotes.Factory.scanChangeIds(repo), done, failed);
+    } catch (IOException e) {
+      logger.atSevere().log(e.getMessage());
+      return null;
+    }
   }
 
   public Callable<Void> reindexProject(
@@ -252,9 +226,10 @@
       Project.NameKey project,
       int slice,
       int slices,
+      ScanResult scanResult,
       Task done,
       Task failed) {
-    return new ProjectIndexer(indexer, project, slice, slices, done, failed);
+    return new ProjectIndexer(indexer, project, slice, slices, scanResult, done, failed);
   }
 
   private class ProjectIndexer implements Callable<Void> {
@@ -262,6 +237,7 @@
     private final Project.NameKey project;
     private final int slice;
     private final int slices;
+    private final ScanResult scanResult;
     private final ProgressMonitor done;
     private final ProgressMonitor failed;
 
@@ -270,32 +246,30 @@
         Project.NameKey project,
         int slice,
         int slices,
+        ScanResult scanResult,
         ProgressMonitor done,
         ProgressMonitor failed) {
       this.indexer = indexer;
       this.project = project;
       this.slice = slice;
       this.slices = slices;
+      this.scanResult = scanResult;
       this.done = done;
       this.failed = failed;
     }
 
     @Override
     public Void call() throws Exception {
-      try (Repository repo = repoManager.openRepository(project)) {
-        OnlineReindexMode.begin();
-
-        // Order of scanning changes is undefined. This is ok if we assume that packfile locality is
-        // not important for indexing, since sites should have a fully populated DiffSummary cache.
-        // It does mean that reindexing after invalidating the DiffSummary cache will be expensive,
-        // but the goal is to invalidate that cache as infrequently as we possibly can. And besides,
-        // we don't have concrete proof that improving packfile locality would help.
-        notesFactory.scan(repo, project, id -> (id.get() % slices) == slice).forEach(r -> index(r));
-      } catch (RepositoryNotFoundException rnfe) {
-        logger.atSevere().log(rnfe.getMessage());
-      } finally {
-        OnlineReindexMode.end();
-      }
+      OnlineReindexMode.begin();
+      // Order of scanning changes is undefined. This is ok if we assume that packfile locality is
+      // not important for indexing, since sites should have a fully populated DiffSummary cache.
+      // It does mean that reindexing after invalidating the DiffSummary cache will be expensive,
+      // but the goal is to invalidate that cache as infrequently as we possibly can. And besides,
+      // we don't have concrete proof that improving packfile locality would help.
+      notesFactory
+          .scan(scanResult, project, id -> (id.get() % slices) == slice)
+          .forEach(r -> index(r));
+      OnlineReindexMode.end();
       return null;
     }
 
@@ -335,4 +309,63 @@
       return "Index all changes of project " + project.get();
     }
   }
+
+  private class SliceCreator {
+    final Set<ProjectSlice> projectSlices = Sets.newConcurrentHashSet();
+    final AtomicInteger changeCount = new AtomicInteger(0);
+    final AtomicInteger projectsFailed = new AtomicInteger(0);
+    final ProgressMonitor pm = new TextProgressMonitor();
+
+    private List<ProjectSlice> create()
+        throws ProjectsCollectionFailure, InterruptedException, ExecutionException {
+      List<ListenableFuture<?>> futures = new ArrayList<>();
+      pm.beginTask("Collecting projects", ProgressMonitor.UNKNOWN);
+      for (Project.NameKey name : projectCache.all()) {
+        futures.add(executor.submit(new ProjectSliceCreator(name)));
+      }
+
+      Futures.allAsList(futures).get();
+
+      if (projectsFailed.get() > projectCache.all().size() / 2) {
+        throw new ProjectsCollectionFailure(
+            "Over 50%% of the projects could not be collected: aborted");
+      }
+
+      pm.endTask();
+      setTotalWork(changeCount.get());
+      return projectSlices.stream().collect(Collectors.toList());
+    }
+
+    private class ProjectSliceCreator implements Callable<Void> {
+      final Project.NameKey name;
+
+      public ProjectSliceCreator(Project.NameKey name) {
+        this.name = name;
+      }
+
+      @Override
+      public Void call() throws IOException {
+        try (Repository repo = repoManager.openRepository(name)) {
+          ScanResult sr = ChangeNotes.Factory.scanChangeIds(repo);
+          int size = sr.all().size();
+          if (size > 0) {
+            changeCount.addAndGet(size);
+            int slices = 1 + size / PROJECT_SLICE_MAX_REFS;
+            if (slices > 1) {
+              verboseWriter.println(
+                  "Submitting " + name + " for indexing in " + slices + " slices");
+            }
+            for (int slice = 0; slice < slices; slice++) {
+              projectSlices.add(ProjectSlice.create(name, slice, slices, sr));
+            }
+          }
+        } catch (IOException e) {
+          logger.atSevere().withCause(e).log("Error collecting project %s", name);
+          projectsFailed.incrementAndGet();
+        }
+        pm.update(1);
+        return null;
+      }
+    }
+  }
 }
diff --git a/java/com/google/gerrit/server/index/change/ChangeIndexer.java b/java/com/google/gerrit/server/index/change/ChangeIndexer.java
index e0f6bec..a088af0 100644
--- a/java/com/google/gerrit/server/index/change/ChangeIndexer.java
+++ b/java/com/google/gerrit/server/index/change/ChangeIndexer.java
@@ -30,6 +30,7 @@
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.index.IndexExecutor;
 import com.google.gerrit.server.index.StalenessCheckResult;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.logging.TraceContext;
 import com.google.gerrit.server.logging.TraceContext.TraceTimer;
@@ -78,6 +79,7 @@
   private final PluginSetContext<ChangeIndexedListener> indexedListeners;
   private final StalenessChecker stalenessChecker;
   private final boolean autoReindexIfStale;
+  private final IsFirstInsertForEntry isFirstInsertForEntry;
 
   private final Set<IndexTask> queuedIndexTasks =
       Collections.newSetFromMap(new ConcurrentHashMap<>());
@@ -94,7 +96,8 @@
       StalenessChecker stalenessChecker,
       @IndexExecutor(BATCH) ListeningExecutorService batchExecutor,
       @Assisted ListeningExecutorService executor,
-      @Assisted ChangeIndex index) {
+      @Assisted ChangeIndex index,
+      IsFirstInsertForEntry isFirstInsertForEntry) {
     this.executor = executor;
     this.changeDataFactory = changeDataFactory;
     this.notesFactory = notesFactory;
@@ -105,6 +108,7 @@
     this.autoReindexIfStale = autoReindexIfStale(cfg);
     this.index = index;
     this.indexes = null;
+    this.isFirstInsertForEntry = isFirstInsertForEntry;
   }
 
   @AssistedInject
@@ -117,7 +121,8 @@
       StalenessChecker stalenessChecker,
       @IndexExecutor(BATCH) ListeningExecutorService batchExecutor,
       @Assisted ListeningExecutorService executor,
-      @Assisted ChangeIndexCollection indexes) {
+      @Assisted ChangeIndexCollection indexes,
+      IsFirstInsertForEntry isFirstInsertForEntry) {
     this.executor = executor;
     this.changeDataFactory = changeDataFactory;
     this.notesFactory = notesFactory;
@@ -128,6 +133,7 @@
     this.autoReindexIfStale = autoReindexIfStale(cfg);
     this.index = null;
     this.indexes = indexes;
+    this.isFirstInsertForEntry = isFirstInsertForEntry;
   }
 
   private static boolean autoReindexIfStale(Config cfg) {
@@ -198,21 +204,25 @@
   }
 
   private void indexImpl(ChangeData cd) {
-    logger.atFine().log("Replace change %d in index.", cd.getId().get());
+    logger.atFine().log("Reindex change %d in index.", cd.getId().get());
     for (Index<?, ChangeData> i : getWriteIndexes()) {
       try (TraceTimer traceTimer =
           TraceContext.newTimer(
-              "Replacing change in index",
+              "Reindexing change in index",
               Metadata.builder()
                   .changeId(cd.getId().get())
                   .patchSetId(cd.currentPatchSet().number())
                   .indexVersion(i.getSchema().getVersion())
                   .build())) {
-        i.replace(cd);
+        if (isFirstInsertForEntry.equals(isFirstInsertForEntry.YES)) {
+          i.insert(cd);
+        } else {
+          i.replace(cd);
+        }
       } catch (RuntimeException e) {
         throw new StorageException(
             String.format(
-                "Failed to replace change %d in index version %d (current patch set = %d)",
+                "Failed to reindex change %d in index version %d (current patch set = %d)",
                 cd.getId().get(), i.getSchema().getVersion(), cd.currentPatchSet().number()),
             e);
       }
diff --git a/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java b/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
index b3ef679..075a4ce 100644
--- a/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
+++ b/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
@@ -30,6 +30,7 @@
 import com.google.gerrit.server.group.db.Groups;
 import com.google.gerrit.server.group.db.GroupsNoteDbConsistencyChecker;
 import com.google.gerrit.server.index.IndexExecutor;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
@@ -54,15 +55,18 @@
   private final ListeningExecutorService executor;
   private final GroupCache groupCache;
   private final Groups groups;
+  private final IsFirstInsertForEntry isFirstInsertForEntry;
 
   @Inject
   AllGroupsIndexer(
       @IndexExecutor(BATCH) ListeningExecutorService executor,
       GroupCache groupCache,
-      Groups groups) {
+      Groups groups,
+      IsFirstInsertForEntry isFirstInsertForEntry) {
     this.executor = executor;
     this.groupCache = groupCache;
     this.groups = groups;
+    this.isFirstInsertForEntry = isFirstInsertForEntry;
   }
 
   @Override
@@ -96,9 +100,14 @@
           executor.submit(
               () -> {
                 try {
+                  groupCache.evict(uuid);
                   InternalGroup internalGroup = reindexedGroups.get(uuid);
                   if (internalGroup != null) {
-                    index.replace(internalGroup);
+                    if (isFirstInsertForEntry.equals(isFirstInsertForEntry.YES)) {
+                      index.insert(internalGroup);
+                    } else {
+                      index.replace(internalGroup);
+                    }
                   } else {
                     index.delete(uuid);
 
diff --git a/java/com/google/gerrit/server/index/options/IsFirstInsertForEntry.java b/java/com/google/gerrit/server/index/options/IsFirstInsertForEntry.java
new file mode 100644
index 0000000..f943309
--- /dev/null
+++ b/java/com/google/gerrit/server/index/options/IsFirstInsertForEntry.java
@@ -0,0 +1,26 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.index.options;
+
+/**
+ * This enum should be injected and checked to decide on which operation ({@link
+ * com.google.gerrit.index.Index#replace(Object) replace()} or {@link
+ * com.google.gerrit.index.Index#insert(Object) insert()}) should be performed on a specific {@link
+ * com.google.gerrit.index.Index index}.
+ */
+public enum IsFirstInsertForEntry {
+  YES,
+  NO
+}
diff --git a/java/com/google/gerrit/server/index/project/AllProjectsIndexer.java b/java/com/google/gerrit/server/index/project/AllProjectsIndexer.java
index 0e4b688..86c7e94 100644
--- a/java/com/google/gerrit/server/index/project/AllProjectsIndexer.java
+++ b/java/com/google/gerrit/server/index/project/AllProjectsIndexer.java
@@ -27,6 +27,7 @@
 import com.google.gerrit.index.project.ProjectData;
 import com.google.gerrit.index.project.ProjectIndex;
 import com.google.gerrit.server.index.IndexExecutor;
+import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -48,12 +49,16 @@
 
   private final ListeningExecutorService executor;
   private final ProjectCache projectCache;
+  private final IsFirstInsertForEntry isFirstInsertForEntry;
 
   @Inject
   AllProjectsIndexer(
-      @IndexExecutor(BATCH) ListeningExecutorService executor, ProjectCache projectCache) {
+      @IndexExecutor(BATCH) ListeningExecutorService executor,
+      ProjectCache projectCache,
+      IsFirstInsertForEntry isFirstInsertForEntry) {
     this.executor = executor;
     this.projectCache = projectCache;
+    this.isFirstInsertForEntry = isFirstInsertForEntry;
   }
 
   @Override
@@ -79,8 +84,13 @@
               () -> {
                 try {
                   projectCache.evict(name);
-                  index.replace(
-                      projectCache.get(name).orElseThrow(illegalState(name)).toProjectData());
+                  ProjectData projectData =
+                      projectCache.get(name).orElseThrow(illegalState(name)).toProjectData();
+                  if (isFirstInsertForEntry.equals(isFirstInsertForEntry.YES)) {
+                    index.insert(projectData);
+                  } else {
+                    index.replace(projectData);
+                  }
                   verboseWriter.println("Reindexed " + desc);
                   done.incrementAndGet();
                 } catch (Exception e) {
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotes.java b/java/com/google/gerrit/server/notedb/ChangeNotes.java
index 2e4dfa5..6500d92 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotes.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotes.java
@@ -112,6 +112,29 @@
       this.projectCache = projectCache;
     }
 
+    @AutoValue
+    public abstract static class ScanResult {
+      abstract ImmutableSet<Change.Id> fromPatchSetRefs();
+
+      abstract ImmutableSet<Change.Id> fromMetaRefs();
+
+      public SetView<Change.Id> all() {
+        return Sets.union(fromPatchSetRefs(), fromMetaRefs());
+      }
+    }
+
+    public static ScanResult scanChangeIds(Repository repo) throws IOException {
+      ImmutableSet.Builder<Change.Id> fromPs = ImmutableSet.builder();
+      ImmutableSet.Builder<Change.Id> fromMeta = ImmutableSet.builder();
+      for (Ref r : repo.getRefDatabase().getRefsByPrefix(RefNames.REFS_CHANGES)) {
+        Change.Id id = Change.Id.fromRef(r.getName());
+        if (id != null) {
+          (r.getName().endsWith(RefNames.META_SUFFIX) ? fromMeta : fromPs).add(id);
+        }
+      }
+      return new AutoValue_ChangeNotes_Factory_ScanResult(fromPs.build(), fromMeta.build());
+    }
+
     public ChangeNotes createChecked(Change c) {
       return createChecked(c.getProject(), c.getId());
     }
@@ -271,8 +294,11 @@
     public Stream<ChangeNotesResult> scan(
         Repository repo, Project.NameKey project, Predicate<Change.Id> changeIdPredicate)
         throws IOException {
-      ScanResult sr = scanChangeIds(repo);
+      return scan(scanChangeIds(repo), project, changeIdPredicate);
+    }
 
+    public Stream<ChangeNotesResult> scan(
+        ScanResult sr, Project.NameKey project, Predicate<Change.Id> changeIdPredicate) {
       Stream<Change.Id> idStream = sr.all().stream();
       if (changeIdPredicate != null) {
         idStream = idStream.filter(changeIdPredicate);
@@ -344,29 +370,6 @@
       @Nullable
       abstract ChangeNotes maybeNotes();
     }
-
-    @AutoValue
-    abstract static class ScanResult {
-      abstract ImmutableSet<Change.Id> fromPatchSetRefs();
-
-      abstract ImmutableSet<Change.Id> fromMetaRefs();
-
-      SetView<Change.Id> all() {
-        return Sets.union(fromPatchSetRefs(), fromMetaRefs());
-      }
-    }
-
-    private static ScanResult scanChangeIds(Repository repo) throws IOException {
-      ImmutableSet.Builder<Change.Id> fromPs = ImmutableSet.builder();
-      ImmutableSet.Builder<Change.Id> fromMeta = ImmutableSet.builder();
-      for (Ref r : repo.getRefDatabase().getRefsByPrefix(RefNames.REFS_CHANGES)) {
-        Change.Id id = Change.Id.fromRef(r.getName());
-        if (id != null) {
-          (r.getName().endsWith(RefNames.META_SUFFIX) ? fromMeta : fromPs).add(id);
-        }
-      }
-      return new AutoValue_ChangeNotes_Factory_ScanResult(fromPs.build(), fromMeta.build());
-    }
   }
 
   private final boolean shouldExist;
diff --git a/java/com/google/gerrit/server/project/ProjectCache.java b/java/com/google/gerrit/server/project/ProjectCache.java
index cd41ce5..5124e0e 100644
--- a/java/com/google/gerrit/server/project/ProjectCache.java
+++ b/java/com/google/gerrit/server/project/ProjectCache.java
@@ -59,18 +59,25 @@
   Optional<ProjectState> get(@Nullable Project.NameKey projectName) throws StorageException;
 
   /**
+   * Invalidate the cached information about the given project.
+   *
+   * @param p the NameKey of the project that is being evicted
+   */
+  void evict(Project.NameKey p);
+
+  /**
    * Invalidate the cached information about the given project, and triggers reindexing for it
    *
    * @param p project that is being evicted
    */
-  void evict(Project p);
+  void evictAndReindex(Project p);
 
   /**
    * Invalidate the cached information about the given project, and triggers reindexing for it
    *
    * @param p the NameKey of the project that is being evicted
    */
-  void evict(Project.NameKey p);
+  void evictAndReindex(Project.NameKey p);
 
   /**
    * Remove information about the given project from the cache. It will no longer be returned from
diff --git a/java/com/google/gerrit/server/project/ProjectCacheImpl.java b/java/com/google/gerrit/server/project/ProjectCacheImpl.java
index 1b11ba2..5ea95fb 100644
--- a/java/com/google/gerrit/server/project/ProjectCacheImpl.java
+++ b/java/com/google/gerrit/server/project/ProjectCacheImpl.java
@@ -209,16 +209,21 @@
   }
 
   @Override
-  public void evict(Project p) {
-    evict(p.getNameKey());
-  }
-
-  @Override
   public void evict(Project.NameKey p) {
     if (p != null) {
       logger.atFine().log("Evict project '%s'", p.get());
       inMemoryProjectCache.invalidate(p);
     }
+  }
+
+  @Override
+  public void evictAndReindex(Project p) {
+    evictAndReindex(p.getNameKey());
+  }
+
+  @Override
+  public void evictAndReindex(Project.NameKey p) {
+    evict(p);
     indexer.get().index(p);
   }
 
@@ -239,7 +244,7 @@
     } finally {
       listLock.unlock();
     }
-    evict(name);
+    evictAndReindex(name);
   }
 
   @Override
diff --git a/java/com/google/gerrit/server/restapi/config/GetCache.java b/java/com/google/gerrit/server/restapi/config/GetCache.java
index 93600ea..5dd3d3d 100644
--- a/java/com/google/gerrit/server/restapi/config/GetCache.java
+++ b/java/com/google/gerrit/server/restapi/config/GetCache.java
@@ -16,6 +16,7 @@
 
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestReadView;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gerrit.server.config.CacheResource;
 import com.google.inject.Singleton;
 
@@ -23,7 +24,7 @@
 public class GetCache implements RestReadView<CacheResource> {
 
   @Override
-  public Response<ListCaches.CacheInfo> apply(CacheResource rsrc) {
-    return Response.ok(new ListCaches.CacheInfo(rsrc.getName(), rsrc.getCache()));
+  public Response<CacheInfo> apply(CacheResource rsrc) {
+    return Response.ok(new CacheInfo(rsrc.getName(), rsrc.getCache()));
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/config/ListCaches.java b/java/com/google/gerrit/server/restapi/config/ListCaches.java
index ccafbe8..ffc65c9 100644
--- a/java/com/google/gerrit/server/restapi/config/ListCaches.java
+++ b/java/com/google/gerrit/server/restapi/config/ListCaches.java
@@ -22,7 +22,6 @@
 import static java.util.stream.Collectors.joining;
 
 import com.google.common.cache.Cache;
-import com.google.common.cache.CacheStats;
 import com.google.common.collect.Streams;
 import com.google.gerrit.extensions.annotations.RequiresAnyCapability;
 import com.google.gerrit.extensions.registration.DynamicMap;
@@ -30,7 +29,7 @@
 import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestReadView;
-import com.google.gerrit.server.cache.PersistentCache;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gerrit.server.config.ConfigResource;
 import com.google.inject.Inject;
 import java.util.Map;
@@ -87,118 +86,4 @@
     }
     return Response.ok(cacheNames.collect(toImmutableList()));
   }
-
-  public enum CacheType {
-    MEM,
-    DISK
-  }
-
-  public static class CacheInfo {
-    public String name;
-    public CacheType type;
-    public EntriesInfo entries;
-    public String averageGet;
-    public HitRatioInfo hitRatio;
-
-    public CacheInfo(Cache<?, ?> cache) {
-      this(null, cache);
-    }
-
-    public CacheInfo(String name, Cache<?, ?> cache) {
-      this.name = name;
-
-      CacheStats stat = cache.stats();
-
-      entries = new EntriesInfo();
-      entries.setMem(cache.size());
-
-      averageGet = duration(stat.averageLoadPenalty());
-
-      hitRatio = new HitRatioInfo();
-      hitRatio.setMem(stat.hitCount(), stat.requestCount());
-
-      if (cache instanceof PersistentCache) {
-        type = CacheType.DISK;
-        PersistentCache.DiskStats diskStats = ((PersistentCache) cache).diskStats();
-        entries.setDisk(diskStats.size());
-        entries.setSpace(diskStats.space());
-        hitRatio.setDisk(diskStats.hitCount(), diskStats.requestCount());
-      } else {
-        type = CacheType.MEM;
-      }
-    }
-
-    private static String duration(double ns) {
-      if (ns < 0.5) {
-        return null;
-      }
-      String suffix = "ns";
-      if (ns >= 1000.0) {
-        ns /= 1000.0;
-        suffix = "us";
-      }
-      if (ns >= 1000.0) {
-        ns /= 1000.0;
-        suffix = "ms";
-      }
-      if (ns >= 1000.0) {
-        ns /= 1000.0;
-        suffix = "s";
-      }
-      return String.format("%4.1f%s", ns, suffix).trim();
-    }
-  }
-
-  public static class EntriesInfo {
-    public Long mem;
-    public Long disk;
-    public String space;
-
-    public void setMem(long mem) {
-      this.mem = mem != 0 ? mem : null;
-    }
-
-    public void setDisk(long disk) {
-      this.disk = disk != 0 ? disk : null;
-    }
-
-    public void setSpace(double value) {
-      space = bytes(value);
-    }
-
-    private static String bytes(double value) {
-      value /= 1024;
-      String suffix = "k";
-
-      if (value > 1024) {
-        value /= 1024;
-        suffix = "m";
-      }
-      if (value > 1024) {
-        value /= 1024;
-        suffix = "g";
-      }
-      return String.format("%1$6.2f%2$s", value, suffix).trim();
-    }
-  }
-
-  public static class HitRatioInfo {
-    public Integer mem;
-    public Integer disk;
-
-    public void setMem(long value, long total) {
-      mem = percent(value, total);
-    }
-
-    public void setDisk(long value, long total) {
-      disk = percent(value, total);
-    }
-
-    private static Integer percent(long value, long total) {
-      if (total <= 0) {
-        return null;
-      }
-      return (int) ((100 * value) / total);
-    }
-  }
 }
diff --git a/java/com/google/gerrit/server/restapi/project/CreateLabel.java b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
index 2ae1b05..025ff50 100644
--- a/java/com/google/gerrit/server/restapi/project/CreateLabel.java
+++ b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
@@ -101,7 +101,7 @@
 
       config.commit(md);
 
-      projectCache.evict(rsrc.getProjectState().getProject());
+      projectCache.evictAndReindex(rsrc.getProjectState().getProject());
 
       return Response.created(LabelDefinitionJson.format(rsrc.getNameKey(), labelType));
     }
diff --git a/java/com/google/gerrit/server/restapi/project/DeleteLabel.java b/java/com/google/gerrit/server/restapi/project/DeleteLabel.java
index 531640c..8a1927a 100644
--- a/java/com/google/gerrit/server/restapi/project/DeleteLabel.java
+++ b/java/com/google/gerrit/server/restapi/project/DeleteLabel.java
@@ -90,7 +90,7 @@
       config.commit(md);
     }
 
-    projectCache.evict(rsrc.getProject().getProjectState().getProject());
+    projectCache.evictAndReindex(rsrc.getProject().getProjectState().getProject());
 
     return Response.none();
   }
diff --git a/java/com/google/gerrit/server/restapi/project/GetAccess.java b/java/com/google/gerrit/server/restapi/project/GetAccess.java
index a79439c..651e7f0 100644
--- a/java/com/google/gerrit/server/restapi/project/GetAccess.java
+++ b/java/com/google/gerrit/server/restapi/project/GetAccess.java
@@ -153,12 +153,12 @@
       if (config.updateGroupNames(groupBackend)) {
         md.setMessage("Update group names\n");
         config.commit(md);
-        projectCache.evict(config.getProject());
+        projectCache.evictAndReindex(config.getProject());
         projectState = projectCache.get(projectName).orElseThrow(illegalState(projectName));
         perm = permissionBackend.currentUser().project(projectName);
       } else if (config.getRevision() != null
           && !config.getRevision().equals(projectState.getConfig().getRevision().orElse(null))) {
-        projectCache.evict(config.getProject());
+        projectCache.evictAndReindex(config.getProject());
         projectState = projectCache.get(projectName).orElseThrow(illegalState(projectName));
         perm = permissionBackend.currentUser().project(projectName);
       }
diff --git a/java/com/google/gerrit/server/restapi/project/PostLabels.java b/java/com/google/gerrit/server/restapi/project/PostLabels.java
index 0c42ab2..b72e10f 100644
--- a/java/com/google/gerrit/server/restapi/project/PostLabels.java
+++ b/java/com/google/gerrit/server/restapi/project/PostLabels.java
@@ -139,7 +139,7 @@
 
       if (dirty) {
         config.commit(md);
-        projectCache.evict(rsrc.getProjectState().getProject());
+        projectCache.evictAndReindex(rsrc.getProjectState().getProject());
       }
     }
 
diff --git a/java/com/google/gerrit/server/restapi/project/PutConfig.java b/java/com/google/gerrit/server/restapi/project/PutConfig.java
index afa08cd..0770bda 100644
--- a/java/com/google/gerrit/server/restapi/project/PutConfig.java
+++ b/java/com/google/gerrit/server/restapi/project/PutConfig.java
@@ -164,7 +164,7 @@
       md.setMessage("Modified project settings\n");
       try {
         projectConfig.commit(md);
-        projectCache.evict(projectConfig.getProject());
+        projectCache.evictAndReindex(projectConfig.getProject());
         md.getRepository().setGitwebDescription(projectConfig.getProject().getDescription());
       } catch (IOException e) {
         if (e.getCause() instanceof ConfigInvalidException) {
diff --git a/java/com/google/gerrit/server/restapi/project/PutDescription.java b/java/com/google/gerrit/server/restapi/project/PutDescription.java
index a65c626..ec42035 100644
--- a/java/com/google/gerrit/server/restapi/project/PutDescription.java
+++ b/java/com/google/gerrit/server/restapi/project/PutDescription.java
@@ -84,7 +84,7 @@
       md.setAuthor(user);
       md.setMessage(msg);
       config.commit(md);
-      cache.evict(resource.getProjectState().getProject());
+      cache.evictAndReindex(resource.getProjectState().getProject());
       md.getRepository().setGitwebDescription(config.getProject().getDescription());
 
       return Strings.isNullOrEmpty(config.getProject().getDescription())
diff --git a/java/com/google/gerrit/server/restapi/project/SetAccess.java b/java/com/google/gerrit/server/restapi/project/SetAccess.java
index 794cae8..07dbeca 100644
--- a/java/com/google/gerrit/server/restapi/project/SetAccess.java
+++ b/java/com/google/gerrit/server/restapi/project/SetAccess.java
@@ -125,7 +125,7 @@
       }
 
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
       createGroupPermissionSyncer.syncIfNeeded();
     } catch (InvalidNameException e) {
       throw new BadRequestException(e.toString());
diff --git a/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java b/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
index 5aef76a..853d7df 100644
--- a/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
+++ b/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
@@ -115,7 +115,7 @@
       md.setAuthor(rsrc.getUser().asIdentifiedUser());
       md.setMessage(msg);
       config.commit(md);
-      cache.evict(rsrc.getProjectState().getProject());
+      cache.evictAndReindex(rsrc.getProjectState().getProject());
 
       if (target != null) {
         Response<DashboardInfo> response = get.get().apply(target);
diff --git a/java/com/google/gerrit/server/restapi/project/SetLabel.java b/java/com/google/gerrit/server/restapi/project/SetLabel.java
index b1bcb15..34b6812 100644
--- a/java/com/google/gerrit/server/restapi/project/SetLabel.java
+++ b/java/com/google/gerrit/server/restapi/project/SetLabel.java
@@ -93,7 +93,7 @@
             config.getLabelSections().get(newName.isEmpty() ? labelType.getName() : newName);
 
         config.commit(md);
-        projectCache.evict(rsrc.getProject().getProjectState().getProject());
+        projectCache.evictAndReindex(rsrc.getProject().getProjectState().getProject());
       }
     }
     return Response.ok(LabelDefinitionJson.format(rsrc.getProject().getNameKey(), labelType));
diff --git a/java/com/google/gerrit/server/restapi/project/SetParent.java b/java/com/google/gerrit/server/restapi/project/SetParent.java
index 91c29f5..ef31dc5 100644
--- a/java/com/google/gerrit/server/restapi/project/SetParent.java
+++ b/java/com/google/gerrit/server/restapi/project/SetParent.java
@@ -114,7 +114,7 @@
       md.setAuthor(user);
       md.setMessage(msg);
       config.commit(md);
-      cache.evict(rsrc.getProjectState().getProject());
+      cache.evictAndReindex(rsrc.getProjectState().getProject());
 
       Project.NameKey parent = config.getProject().getParent(allProjects);
       requireNonNull(parent);
diff --git a/java/com/google/gerrit/server/submit/SubmitStrategyOp.java b/java/com/google/gerrit/server/submit/SubmitStrategyOp.java
index 69207ac..3a04b82 100644
--- a/java/com/google/gerrit/server/submit/SubmitStrategyOp.java
+++ b/java/com/google/gerrit/server/submit/SubmitStrategyOp.java
@@ -487,7 +487,7 @@
       // TODO(dborowitz): Move to BatchUpdate? Would also allow us to run once
       // per project even if multiple changes to refs/meta/config are submitted.
       if (RefNames.REFS_CONFIG.equals(getDest().branch())) {
-        args.projectCache.evict(getProject());
+        args.projectCache.evictAndReindex(getProject());
         ProjectState p =
             args.projectCache.get(getProject()).orElseThrow(illegalState(getProject()));
         try (Repository git = args.repoManager.openRepository(getProject())) {
diff --git a/java/com/google/gerrit/sshd/commands/ShowCaches.java b/java/com/google/gerrit/sshd/commands/ShowCaches.java
index 979be1b..02956f7 100644
--- a/java/com/google/gerrit/sshd/commands/ShowCaches.java
+++ b/java/com/google/gerrit/sshd/commands/ShowCaches.java
@@ -24,6 +24,8 @@
 import com.google.gerrit.extensions.events.LifecycleListener;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.cache.CacheDisplay;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gerrit.server.config.ConfigResource;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
@@ -35,8 +37,6 @@
 import com.google.gerrit.server.restapi.config.GetSummary.TaskSummaryInfo;
 import com.google.gerrit.server.restapi.config.GetSummary.ThreadSummaryInfo;
 import com.google.gerrit.server.restapi.config.ListCaches;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheType;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.gerrit.sshd.CommandMetaData;
 import com.google.gerrit.sshd.SshCommand;
@@ -123,52 +123,8 @@
     stdout.format("%-25s %-20s   uptime %16s\n", "", "", uptime(now.getTime() - serverStarted));
     stdout.print('\n');
 
-    stdout.print(
-        String.format( //
-            "%1s %-" + nw + "s|%-21s|  %-5s |%-9s|\n" //
-            ,
-            "" //
-            ,
-            "Name" //
-            ,
-            "Entries" //
-            ,
-            "AvgGet" //
-            ,
-            "Hit Ratio" //
-            ));
-    stdout.print(
-        String.format( //
-            "%1s %-" + nw + "s|%6s %6s %7s|  %-5s  |%-4s %-4s|\n" //
-            ,
-            "" //
-            ,
-            "" //
-            ,
-            "Mem" //
-            ,
-            "Disk" //
-            ,
-            "Space" //
-            ,
-            "" //
-            ,
-            "Mem" //
-            ,
-            "Disk" //
-            ));
-    stdout.print("--");
-    for (int i = 0; i < nw; i++) {
-      stdout.print('-');
-    }
-    stdout.print("+---------------------+---------+---------+\n");
-
     try {
-      Collection<CacheInfo> caches = getCaches();
-      printMemoryCoreCaches(caches);
-      printMemoryPluginCaches(caches);
-      printDiskCaches(caches);
-      stdout.print('\n');
+      new CacheDisplay(stdout, nw, getCaches()).displayCaches();
 
       boolean showJvm;
       try {
@@ -209,52 +165,6 @@
     return caches.values();
   }
 
-  private void printMemoryCoreCaches(Collection<CacheInfo> caches) {
-    for (CacheInfo cache : caches) {
-      if (!cache.name.contains("-") && CacheType.MEM.equals(cache.type)) {
-        printCache(cache);
-      }
-    }
-  }
-
-  private void printMemoryPluginCaches(Collection<CacheInfo> caches) {
-    for (CacheInfo cache : caches) {
-      if (cache.name.contains("-") && CacheType.MEM.equals(cache.type)) {
-        printCache(cache);
-      }
-    }
-  }
-
-  private void printDiskCaches(Collection<CacheInfo> caches) {
-    for (CacheInfo cache : caches) {
-      if (CacheType.DISK.equals(cache.type)) {
-        printCache(cache);
-      }
-    }
-  }
-
-  private void printCache(CacheInfo cache) {
-    stdout.print(
-        String.format(
-            "%1s %-" + nw + "s|%6s %6s %7s| %7s |%4s %4s|\n",
-            CacheType.DISK.equals(cache.type) ? "D" : "",
-            cache.name,
-            nullToEmpty(cache.entries.mem),
-            nullToEmpty(cache.entries.disk),
-            Strings.nullToEmpty(cache.entries.space),
-            Strings.nullToEmpty(cache.averageGet),
-            formatAsPercent(cache.hitRatio.mem),
-            formatAsPercent(cache.hitRatio.disk)));
-  }
-
-  private static String nullToEmpty(Long l) {
-    return l != null ? String.valueOf(l) : "";
-  }
-
-  private static String formatAsPercent(Integer i) {
-    return i != null ? String.valueOf(i) + "%" : "";
-  }
-
   private void memSummary(MemSummaryInfo memSummary) {
     stdout.format(
         "Mem: %s total = %s used + %s free + %s buffers\n",
diff --git a/javatests/com/google/gerrit/acceptance/ProjectResetterTest.java b/javatests/com/google/gerrit/acceptance/ProjectResetterTest.java
index ff9bac9..7d04558 100644
--- a/javatests/com/google/gerrit/acceptance/ProjectResetterTest.java
+++ b/javatests/com/google/gerrit/acceptance/ProjectResetterTest.java
@@ -231,7 +231,7 @@
       updateRef(repo2, metaConfig);
     }
 
-    verify(projectCache, only()).evict(project2);
+    verify(projectCache, only()).evictAndReindex(project2);
   }
 
   @Test
@@ -248,7 +248,7 @@
       createRef(repo2, RefNames.REFS_CONFIG);
     }
 
-    verify(projectCache, only()).evict(project2);
+    verify(projectCache, only()).evictAndReindex(project2);
   }
 
   @Test
diff --git a/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java b/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
index 5279ba1..9b77b01 100644
--- a/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
@@ -71,7 +71,7 @@
       config.updateProject(
           p -> p.setBooleanConfig(BooleanProjectConfig.USE_CONTRIBUTOR_AGREEMENTS, value));
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
   }
 
diff --git a/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java b/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
index dd70d4a..0f51095 100644
--- a/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
@@ -989,7 +989,7 @@
       ProjectConfig config = projectConfigFactory.read(md);
       config.renameGroup(AccountGroup.uuid(group.id), newName);
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
 
     Optional<String> afterRename =
diff --git a/javatests/com/google/gerrit/acceptance/git/AbstractSubmoduleSubscription.java b/javatests/com/google/gerrit/acceptance/git/AbstractSubmoduleSubscription.java
index 415aa79..c3bcbd3 100644
--- a/javatests/com/google/gerrit/acceptance/git/AbstractSubmoduleSubscription.java
+++ b/javatests/com/google/gerrit/acceptance/git/AbstractSubmoduleSubscription.java
@@ -226,7 +226,7 @@
       ObjectId oldId = pc.getRevision();
       ObjectId newId = pc.commit(md);
       assertThat(newId).isNotEqualTo(oldId);
-      projectCache.evict(pc.getProject());
+      projectCache.evictAndReindex(pc.getProject());
     }
   }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/CacheOperationsIT.java b/javatests/com/google/gerrit/acceptance/rest/config/CacheOperationsIT.java
index daeb032..e4b4e4a 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/CacheOperationsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/CacheOperationsIT.java
@@ -25,7 +25,7 @@
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.common.data.GlobalCapability;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gerrit.server.restapi.config.PostCaches;
 import com.google.inject.Inject;
 import java.util.Arrays;
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/FlushCacheIT.java b/javatests/com/google/gerrit/acceptance/rest/config/FlushCacheIT.java
index a161ec4..164f683 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/FlushCacheIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/FlushCacheIT.java
@@ -23,7 +23,7 @@
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.common.data.GlobalCapability;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.inject.Inject;
 import org.junit.Test;
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/GetCacheIT.java b/javatests/com/google/gerrit/acceptance/rest/config/GetCacheIT.java
index 247d63b..8765360 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/GetCacheIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/GetCacheIT.java
@@ -18,8 +18,7 @@
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.RestResponse;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheType;
+import com.google.gerrit.server.cache.CacheInfo;
 import org.junit.Test;
 
 public class GetCacheIT extends AbstractDaemonTest {
@@ -31,7 +30,7 @@
     CacheInfo result = newGson().fromJson(r.getReader(), CacheInfo.class);
 
     assertThat(result.name).isEqualTo("accounts");
-    assertThat(result.type).isEqualTo(CacheType.MEM);
+    assertThat(result.type).isEqualTo(CacheInfo.CacheType.MEM);
     assertThat(result.entries.mem).isAtLeast(1L);
     assertThat(result.averageGet).isNotNull();
     assertThat(result.averageGet).endsWith("s");
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java b/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
index 8baeffc..be21436 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
@@ -21,8 +21,7 @@
 import com.google.common.io.BaseEncoding;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.RestResponse;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
-import com.google.gerrit.server.restapi.config.ListCaches.CacheType;
+import com.google.gerrit.server.cache.CacheInfo;
 import com.google.gson.reflect.TypeToken;
 import java.util.Arrays;
 import java.util.List;
@@ -40,7 +39,7 @@
 
     assertThat(result).containsKey("accounts");
     CacheInfo accountsCacheInfo = result.get("accounts");
-    assertThat(accountsCacheInfo.type).isEqualTo(CacheType.MEM);
+    assertThat(accountsCacheInfo.type).isEqualTo(CacheInfo.CacheType.MEM);
     assertThat(accountsCacheInfo.entries.mem).isAtLeast(1L);
     assertThat(accountsCacheInfo.averageGet).isNotNull();
     assertThat(accountsCacheInfo.averageGet).endsWith("s");
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java b/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
index 4a9edba..7442425 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
@@ -179,7 +179,7 @@
     ProjectAccessInfo expected = pApi().access();
 
     grantRevertPermission.execute(newProjectName);
-    projectCache.evict(newProjectName);
+    projectCache.evictAndReindex(newProjectName);
     ProjectAccessInfo actual = pApi().access();
     // Permissions don't change
     assertThat(expected.local).isEqualTo(actual.local);
diff --git a/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java b/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
index cd28ac4..82991b6 100644
--- a/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
+++ b/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
@@ -204,7 +204,7 @@
   private void save(ProjectConfig pc) throws Exception {
     try (MetaDataUpdate md = metaDataUpdateFactory.create(pc.getProject().getNameKey(), user)) {
       pc.commit(md);
-      projectCache.evict(pc.getProject().getNameKey());
+      projectCache.evictAndReindex(pc.getProject().getNameKey());
     }
   }
 
diff --git a/javatests/com/google/gerrit/server/index/change/FakeChangeIndex.java b/javatests/com/google/gerrit/server/index/change/FakeChangeIndex.java
index a23ccab..fc56a3c 100644
--- a/javatests/com/google/gerrit/server/index/change/FakeChangeIndex.java
+++ b/javatests/com/google/gerrit/server/index/change/FakeChangeIndex.java
@@ -74,6 +74,11 @@
   }
 
   @Override
+  public void insert(ChangeData obj) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
   public void replace(ChangeData cd) {
     throw new UnsupportedOperationException();
   }
diff --git a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
index 6c83d25..99ccd31 100644
--- a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
@@ -1051,7 +1051,7 @@
       cfg.upsertLabelType(verified);
       cfg.commit(md);
     }
-    projectCache.evict(project);
+    projectCache.evictAndReindex(project);
 
     String heads = RefNames.REFS_HEADS + "*";
     projectOperations
@@ -2117,7 +2117,7 @@
           });
 
       config.commit(md);
-      projectCache.evict(config.getProject());
+      projectCache.evictAndReindex(config.getProject());
     }
   }
 
diff --git a/plugins/delete-project b/plugins/delete-project
index 549de03..142875a 160000
--- a/plugins/delete-project
+++ b/plugins/delete-project
@@ -1 +1 @@
-Subproject commit 549de033d60b13aaeef45ce5c4bf42be39506268
+Subproject commit 142875ae29b728e4fbad5bc22dc132df37cc4de7
diff --git a/plugins/webhooks b/plugins/webhooks
index 9fc9c2d..dba493b 160000
--- a/plugins/webhooks
+++ b/plugins/webhooks
@@ -1 +1 @@
-Subproject commit 9fc9c2d4e69f7e2701cbcd873977d3312a231a81
+Subproject commit dba493b1679cc07b0f5e3fd9277b306c4693e08a
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.ts b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.ts
index 4a47db6..5abc258 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.ts
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.ts
@@ -1601,7 +1601,7 @@
       params.n = n;
     }
     if (project) {
-      params.p = encodeURIComponent(project);
+      params.p = project;
     }
     return this._restApiHelper.fetchJSON({
       url: '/groups/',