diff --git a/BUILD b/BUILD
index 45afb1a..dc34ede 100644
--- a/BUILD
+++ b/BUILD
@@ -52,7 +52,7 @@
     srcs = glob(["src/test/java/**/*IT.java"]),
     group = "server_cache",
     labels = ["server"],
-    vm_args = ["-Xmx2G"],
+    vm_args = ["-Xmx4g"],
     deps = [
         ":cache-chroniclemap__plugin",
         ":chroniclemap-test-lib",
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCaches.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCaches.java
index 4298a81..948aaee 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCaches.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCaches.java
@@ -27,7 +27,11 @@
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
+import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
 import java.util.stream.Collectors;
 import org.apache.commons.io.FilenameUtils;
@@ -41,12 +45,17 @@
   protected static final String CONFIG_HEADER = "__CONFIG__";
   protected static final String TUNED_INFIX = "_tuned_";
 
+  protected static final Integer MAX_ENTRIES_MULTIPLIER = 2;
+  protected static final Integer PERCENTAGE_SIZE_INCREASE_THRESHOLD = 50;
+
   private final DynamicMap<Cache<?, ?>> cacheMap;
   private final ChronicleMapCacheConfig.Factory configFactory;
   private final Path cacheDir;
   private final AdministerCachePermission adminCachePermission;
 
   private boolean dryRun;
+  private Optional<Long> optionalMaxEntries = Optional.empty();
+  private Set<String> cacheNames = new HashSet<>();
 
   @Inject
   AutoAdjustCaches(
@@ -69,6 +78,18 @@
     this.dryRun = dryRun;
   }
 
+  public Optional<Long> getOptionalMaxEntries() {
+    return optionalMaxEntries;
+  }
+
+  public void setOptionalMaxEntries(Optional<Long> maxEntries) {
+    this.optionalMaxEntries = maxEntries;
+  }
+
+  public void addCacheNames(List<String> cacheNames) {
+    this.cacheNames.addAll(cacheNames);
+  }
+
   protected Config run(@Nullable ProgressMonitor optionalProgressMonitor)
       throws AuthException, PermissionBackendException, IOException {
     ProgressMonitor progressMonitor =
@@ -98,21 +119,24 @@
         long averageValueSize = avgSizes.getValue();
 
         ChronicleMapCacheConfig currCacheConfig = currCache.getConfig();
+        long newMaxEntries = newMaxEntries(currCache);
 
         if (currCacheConfig.getAverageKeySize() == averageKeySize
-            && currCacheConfig.getAverageValueSize() == averageValueSize) {
+            && currCacheConfig.getAverageValueSize() == averageValueSize
+            && currCacheConfig.getMaxEntries() == newMaxEntries) {
           continue;
         }
 
         ChronicleMapCacheConfig newChronicleMapCacheConfig =
-            makeChronicleMapConfig(currCache.getConfig(), averageKeySize, averageValueSize);
+            makeChronicleMapConfig(
+                currCache.getConfig(), newMaxEntries, averageKeySize, averageValueSize);
 
         updateOutputConfig(
             outputChronicleMapConfig,
             cacheName,
             averageKeySize,
             averageValueSize,
-            currCache.getConfig().getMaxEntries(),
+            newMaxEntries,
             currCache.getConfig().getMaxBloatFactor());
 
         if (!dryRun) {
@@ -176,6 +200,7 @@
 
   private ChronicleMapCacheConfig makeChronicleMapConfig(
       ChronicleMapCacheConfig currentChronicleMapConfig,
+      long newMaxEntries,
       long averageKeySize,
       long averageValueSize) {
 
@@ -184,12 +209,30 @@
         resolveNewFile(currentChronicleMapConfig.getPersistedFile().getName()),
         currentChronicleMapConfig.getExpireAfterWrite(),
         currentChronicleMapConfig.getRefreshAfterWrite(),
-        currentChronicleMapConfig.getMaxEntries(),
+        newMaxEntries,
         averageKeySize,
         averageValueSize,
         currentChronicleMapConfig.getMaxBloatFactor());
   }
 
+  private long newMaxEntries(ChronicleMapCacheImpl<Object, Object> currentCache) {
+    return getOptionalMaxEntries()
+        .orElseGet(
+            () -> {
+              double percentageUsedAutoResizes = currentCache.percentageUsedAutoResizes();
+              long currMaxEntries = currentCache.getConfig().getMaxEntries();
+
+              long newMaxEntries = currMaxEntries;
+              if (percentageUsedAutoResizes > PERCENTAGE_SIZE_INCREASE_THRESHOLD) {
+                newMaxEntries = currMaxEntries * MAX_ENTRIES_MULTIPLIER;
+              }
+              logger.atInfo().log(
+                  "Cache '%s' (maxEntries: %s) used %s%% of available space. new maxEntries will be: %s",
+                  currentCache.name(), currMaxEntries, percentageUsedAutoResizes, newMaxEntries);
+              return newMaxEntries;
+            });
+  }
+
   private File resolveNewFile(String currentFileName) {
     String newFileName =
         String.format(
@@ -228,6 +271,7 @@
             pair ->
                 pair.getValue() instanceof ChronicleMapCacheImpl
                     && ((ChronicleMapCacheImpl) pair.getValue()).diskStats().size() > 0)
+        .filter(pair -> cacheNames.isEmpty() ? true : cacheNames.contains(pair.getKey()))
         .collect(
             Collectors.toMap(
                 ImmutablePair::getKey, p -> (ChronicleMapCacheImpl<Object, Object>) p.getValue()));
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesCommand.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesCommand.java
index 7aa240e..580bd98 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesCommand.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesCommand.java
@@ -19,8 +19,11 @@
 import com.google.gerrit.sshd.SshCommand;
 import com.google.inject.Inject;
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.Optional;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.TextProgressMonitor;
+import org.kohsuke.args4j.Argument;
 import org.kohsuke.args4j.Option;
 
 public class AutoAdjustCachesCommand extends SshCommand {
@@ -38,6 +41,24 @@
     autoAdjustCachesEngine.setDryRun(dryRun);
   }
 
+  @Option(
+      name = "--max-entries",
+      aliases = {"-m"},
+      usage = "The number of entries that the new tuned cache is going to hold.")
+  public void setMaxEntries(long maxEntries) {
+    autoAdjustCachesEngine.setOptionalMaxEntries(Optional.of(maxEntries));
+  }
+
+  @Argument(
+      index = 0,
+      required = false,
+      multiValued = true,
+      metaVar = "CACHE_NAME",
+      usage = "name of cache to be adjusted")
+  public void setCacheName(String cacheName) {
+    autoAdjustCachesEngine.addCacheNames(Arrays.asList(cacheName));
+  }
+
   @Inject
   AutoAdjustCachesCommand(AutoAdjustCaches autoAdjustCachesEngine) {
     this.autoAdjustCachesEngine = autoAdjustCachesEngine;
@@ -65,7 +86,7 @@
       stderr.println(e.getLocalizedMessage());
       throw e;
     } catch (IOException e) {
-      logger.atSevere().log("Could not create new cache", e);
+      logger.atSevere().withCause(e).log("Could not create new cache");
       stderr.println(String.format("Could not create new cache : %s", e.getLocalizedMessage()));
     }
   }
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesServlet.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesServlet.java
index b217b0e..49f7a97 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesServlet.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesServlet.java
@@ -24,6 +24,7 @@
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Optional;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
@@ -56,6 +57,16 @@
             .or(() -> Optional.ofNullable(req.getParameter("d")))
             .isPresent());
 
+    autoAdjustCachesEngine.setOptionalMaxEntries(
+        Optional.ofNullable(req.getParameter("max-entries"))
+            .or(() -> Optional.ofNullable(req.getParameter("m")))
+            .map(Long::parseLong));
+
+    String[] cacheNames = req.getParameterValues("CACHE_NAME");
+    if (cacheNames != null) {
+      autoAdjustCachesEngine.addCacheNames(Arrays.asList(cacheNames));
+    }
+
     try {
       Config outputChronicleMapConfig = autoAdjustCachesEngine.run(null);
 
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheFactory.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheFactory.java
index e1eb5ab..1161699 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheFactory.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheFactory.java
@@ -42,7 +42,6 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
-import net.openhft.chronicle.map.ChronicleMap;
 import org.eclipse.jgit.lib.Config;
 
 @Singleton
@@ -105,8 +104,8 @@
 
     ChronicleMapCacheImpl<K, V> cache;
     try {
-      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store =
-          ChronicleMapCacheImpl.createOrRecoverStore(in, config);
+      ChronicleMapStore<K, V> store =
+          ChronicleMapCacheImpl.createOrRecoverStore(in, config, metricMaker);
 
       ChronicleMapCacheLoader<K, V> memLoader =
           new ChronicleMapCacheLoader<>(
@@ -122,8 +121,7 @@
               config,
               metricMaker,
               memLoader,
-              new InMemoryCacheLoadingFromStoreImpl<>(mem, false),
-              store);
+              new InMemoryCacheLoadingFromStoreImpl<>(mem, false));
 
     } catch (IOException e) {
       throw new UncheckedIOException(e);
@@ -158,8 +156,8 @@
     ChronicleMapCacheDefProxy<K, V> def = new ChronicleMapCacheDefProxy<>(in);
 
     try {
-      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store =
-          ChronicleMapCacheImpl.createOrRecoverStore(in, config);
+      ChronicleMapStore<K, V> store =
+          ChronicleMapCacheImpl.createOrRecoverStore(in, config, metricMaker);
 
       ChronicleMapCacheLoader<K, V> memLoader =
           new ChronicleMapCacheLoader<>(
@@ -175,8 +173,7 @@
               config,
               metricMaker,
               memLoader,
-              new InMemoryCacheLoadingFromStoreImpl<>(mem, true),
-              store);
+              new InMemoryCacheLoadingFromStoreImpl<>(mem, true));
     } catch (IOException e) {
       throw new UncheckedIOException(e);
     }
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheImpl.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheImpl.java
index af35c88..b704a7b 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheImpl.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheImpl.java
@@ -39,7 +39,7 @@
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final ChronicleMapCacheConfig config;
-  private final ChronicleMap<KeyWrapper<K>, TimedValue<V>> store;
+  private final ChronicleMapStore<K, V> store;
   private final LongAdder hitCount = new LongAdder();
   private final LongAdder missCount = new LongAdder();
   private final LongAdder loadSuccessCount = new LongAdder();
@@ -52,20 +52,21 @@
 
   ChronicleMapCacheImpl(PersistentCacheDef<K, V> def, ChronicleMapCacheConfig config)
       throws IOException {
+    DisabledMetricMaker metricMaker = new DisabledMetricMaker();
 
     this.cacheDefinition = def;
     this.config = config;
     this.hotEntries =
         new InMemoryLRU<>(
             (int) Math.max(config.getMaxEntries() * config.getpercentageHotKeys() / 100, 1));
-    this.store = createOrRecoverStore(def, config);
+    this.store = createOrRecoverStore(def, config, metricMaker);
     this.memLoader =
         new ChronicleMapCacheLoader<>(
             MoreExecutors.directExecutor(), store, config.getExpireAfterWrite());
     this.mem = memLoader.asInMemoryCacheBypass();
 
-    ChronicleMapStorageMetrics metrics = new ChronicleMapStorageMetrics(new DisabledMetricMaker());
-    metrics.registerCallBackMetrics(def.name(), store, hotEntries);
+    ChronicleMapCacheMetrics metrics = new ChronicleMapCacheMetrics(metricMaker);
+    metrics.registerCallBackMetrics(def.name(), this);
   }
 
   ChronicleMapCacheImpl(
@@ -73,8 +74,7 @@
       ChronicleMapCacheConfig config,
       MetricMaker metricMaker,
       ChronicleMapCacheLoader<K, V> memLoader,
-      InMemoryCache<K, V> mem,
-      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store) {
+      InMemoryCache<K, V> mem) {
 
     this.cacheDefinition = def;
     this.config = config;
@@ -83,15 +83,16 @@
             (int) Math.max(config.getMaxEntries() * config.getpercentageHotKeys() / 100, 1));
     this.memLoader = memLoader;
     this.mem = mem;
-    this.store = store;
+    this.store = memLoader.getStore();
 
-    ChronicleMapStorageMetrics metrics = new ChronicleMapStorageMetrics(metricMaker);
-    metrics.registerCallBackMetrics(def.name(), store, hotEntries);
+    ChronicleMapCacheMetrics metrics = new ChronicleMapCacheMetrics(metricMaker);
+    metrics.registerCallBackMetrics(def.name(), this);
   }
 
   @SuppressWarnings({"unchecked", "cast", "rawtypes"})
-  static <K, V> ChronicleMap<KeyWrapper<K>, TimedValue<V>> createOrRecoverStore(
-      PersistentCacheDef<K, V> def, ChronicleMapCacheConfig config) throws IOException {
+  static <K, V> ChronicleMapStore<K, V> createOrRecoverStore(
+      PersistentCacheDef<K, V> def, ChronicleMapCacheConfig config, MetricMaker metricMaker)
+      throws IOException {
     CacheSerializers.registerCacheDef(def);
 
     final Class<KeyWrapper<K>> keyWrapperClass = (Class<KeyWrapper<K>>) (Class) KeyWrapper.class;
@@ -137,49 +138,29 @@
         store.remainingAutoResizes(),
         store.percentageFreeSpace());
 
-    return store;
+    return new ChronicleMapStore<>(store, config, metricMaker);
   }
 
   protected PersistentCacheDef<K, V> getCacheDefinition() {
     return cacheDefinition;
   }
 
-  private static class ChronicleMapStorageMetrics {
+  private static class ChronicleMapCacheMetrics {
 
     private final MetricMaker metricMaker;
 
-    ChronicleMapStorageMetrics(MetricMaker metricMaker) {
+    ChronicleMapCacheMetrics(MetricMaker metricMaker) {
       this.metricMaker = metricMaker;
     }
 
-    <K, V> void registerCallBackMetrics(
-        String name, ChronicleMap<KeyWrapper<K>, TimedValue<V>> store, InMemoryLRU<K> hotEntries) {
+    <K, V> void registerCallBackMetrics(String name, ChronicleMapCacheImpl<K, V> cache) {
       String sanitizedName = metricMaker.sanitizeMetricName(name);
-      String PERCENTAGE_FREE_SPACE_METRIC =
-          "cache/chroniclemap/percentage_free_space_" + sanitizedName;
-      String REMAINING_AUTORESIZES_METRIC =
-          "cache/chroniclemap/remaining_autoresizes_" + sanitizedName;
       String HOT_KEYS_CAPACITY_METRIC = "cache/chroniclemap/hot_keys_capacity_" + sanitizedName;
       String HOT_KEYS_SIZE_METRIC = "cache/chroniclemap/hot_keys_size_" + sanitizedName;
 
-      metricMaker.newCallbackMetric(
-          PERCENTAGE_FREE_SPACE_METRIC,
-          Long.class,
-          new Description(
-              String.format("The amount of free space in the %s cache as a percentage", name)),
-          () -> (long) store.percentageFreeSpace());
-
-      metricMaker.newCallbackMetric(
-          REMAINING_AUTORESIZES_METRIC,
-          Integer.class,
-          new Description(
-              String.format(
-                  "The number of times the %s cache can automatically expand its capacity", name)),
-          store::remainingAutoResizes);
-
       metricMaker.newConstantMetric(
           HOT_KEYS_CAPACITY_METRIC,
-          hotEntries.getCapacity(),
+          cache.hotEntries.getCapacity(),
           new Description(
               String.format(
                   "The number of hot cache keys for %s cache that can be kept in memory", name)));
@@ -190,7 +171,7 @@
           new Description(
               String.format(
                   "The number of hot cache keys for %s cache that are currently in memory", name)),
-          hotEntries::size);
+          cache.hotEntries::size);
     }
   }
 
@@ -276,8 +257,9 @@
   public void putUnchecked(Object key, Object value, Timestamp created) {
     TimedValue<?> wrappedValue = new TimedValue<>(value, created.toInstant().toEpochMilli());
     KeyWrapper<?> wrappedKey = new KeyWrapper<>(key);
-    store.put((KeyWrapper<K>) wrappedKey, (TimedValue<V>) wrappedValue);
-    mem.put((K) key, (TimedValue<V>) wrappedValue);
+    if (store.tryPut((KeyWrapper<K>) wrappedKey, (TimedValue<V>) wrappedValue)) {
+      mem.put((K) key, (TimedValue<V>) wrappedValue);
+    }
   }
 
   /**
@@ -292,21 +274,26 @@
    */
   @SuppressWarnings("unchecked")
   public void putUnchecked(KeyWrapper<Object> wrappedKey, TimedValue<Object> wrappedValue) {
-    store.put((KeyWrapper<K>) wrappedKey, (TimedValue<V>) wrappedValue);
-    mem.put((K) wrappedKey.getValue(), (TimedValue<V>) wrappedValue);
+    if (store.tryPut((KeyWrapper<K>) wrappedKey, (TimedValue<V>) wrappedValue)) {
+      mem.put((K) wrappedKey.getValue(), (TimedValue<V>) wrappedValue);
+    }
   }
 
   @Override
   public void put(K key, V val) {
     TimedValue<V> timedVal = new TimedValue<>(val);
-    mem.put(key, timedVal);
-    putTimedToStore(key, timedVal);
+    if (putTimedToStore(key, timedVal)) {
+      mem.put(key, timedVal);
+    }
   }
 
-  void putTimedToStore(K key, TimedValue<V> timedVal) {
+  boolean putTimedToStore(K key, TimedValue<V> timedVal) {
     KeyWrapper<K> wrappedKey = new KeyWrapper<>(key);
-    store.put(wrappedKey, timedVal);
-    hotEntries.add(key);
+    boolean putSuccess = store.tryPut(wrappedKey, timedVal);
+    if (putSuccess) {
+      hotEntries.add(key);
+    }
+    return putSuccess;
   }
 
   public void prune() {
@@ -392,4 +379,12 @@
   public void close() {
     store.close();
   }
+
+  public double percentageUsedAutoResizes() {
+    return store.percentageUsedAutoResizes();
+  }
+
+  public String name() {
+    return store.name();
+  }
 }
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheLoader.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheLoader.java
index 1da3257..9a68780 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheLoader.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheLoader.java
@@ -31,14 +31,13 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.LongAdder;
-import net.openhft.chronicle.map.ChronicleMap;
 
 class ChronicleMapCacheLoader<K, V> extends CacheLoader<K, TimedValue<V>> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final Executor storePersistenceExecutor;
   private final Optional<CacheLoader<K, V>> loader;
-  private final ChronicleMap<KeyWrapper<K>, TimedValue<V>> store;
+  private final ChronicleMapStore<K, V> store;
   private final LongAdder loadSuccessCount = new LongAdder();
   private final LongAdder loadExceptionCount = new LongAdder();
   private final LongAdder totalLoadTime = new LongAdder();
@@ -56,7 +55,7 @@
    */
   ChronicleMapCacheLoader(
       Executor storePersistenceExecutor,
-      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store,
+      ChronicleMapStore<K, V> store,
       CacheLoader<K, V> loader,
       Duration expireAfterWrite) {
     this.storePersistenceExecutor = storePersistenceExecutor;
@@ -73,9 +72,7 @@
    * @param expireAfterWrite maximum lifetime of the data loaded into ChronicleMap
    */
   ChronicleMapCacheLoader(
-      Executor storePersistenceExecutor,
-      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store,
-      Duration expireAfterWrite) {
+      Executor storePersistenceExecutor, ChronicleMapStore<K, V> store, Duration expireAfterWrite) {
     this.storePersistenceExecutor = storePersistenceExecutor;
     this.store = store;
     this.loader = Optional.empty();
@@ -96,9 +93,16 @@
         missCount.increment();
         long start = System.nanoTime();
         TimedValue<V> loadedValue = new TimedValue<>(loader.get().load(key));
-        loadSuccessCount.increment();
         totalLoadTime.add(System.nanoTime() - start);
-        storePersistenceExecutor.execute(() -> store.put(new KeyWrapper<>(key), loadedValue));
+        storePersistenceExecutor.execute(
+            () -> {
+              // Note that we return a loadedValue, even when we
+              // we fail populating the cache with it, to make clients more
+              // resilient to storage cache failures
+              if (store.tryPut(new KeyWrapper<>(key), loadedValue)) {
+                loadSuccessCount.increment();
+              }
+            });
         return loadedValue;
       }
 
@@ -110,6 +114,10 @@
     }
   }
 
+  public ChronicleMapStore<K, V> getStore() {
+    return store;
+  }
+
   TimedValue<V> loadIfPresent(K key) {
     TimedValue<V> h = store.get(new KeyWrapper<>(key));
     if (h != null && !expired(h.getCreated())) {
@@ -133,8 +141,9 @@
         new FutureCallback<V>() {
           @Override
           public void onSuccess(V result) {
-            store.put(new KeyWrapper<>(key), new TimedValue<>(result));
-            loadSuccessCount.increment();
+            if (store.tryPut(new KeyWrapper<>(key), new TimedValue<>(result))) {
+              loadSuccessCount.increment();
+            }
             totalLoadTime.add(System.nanoTime() - start);
           }
 
@@ -175,7 +184,7 @@
 
       @Override
       public void put(K key, TimedValue<V> value) {
-        store.put(new KeyWrapper<>(key), value);
+        store.tryPut(new KeyWrapper<>(key), value);
       }
 
       @Override
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStore.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStore.java
new file mode 100644
index 0000000..0419ca4
--- /dev/null
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStore.java
@@ -0,0 +1,329 @@
+// Copyright (C) 2022 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.googlesource.gerrit.modules.cache.chroniclemap;
+
+import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.metrics.MetricMaker;
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.Type;
+import java.util.Collection;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Consumer;
+import java.util.function.Predicate;
+import net.openhft.chronicle.bytes.BytesStore;
+import net.openhft.chronicle.core.io.Closeable;
+import net.openhft.chronicle.core.util.SerializableFunction;
+import net.openhft.chronicle.hash.Data;
+import net.openhft.chronicle.map.ChronicleMap;
+import net.openhft.chronicle.map.ExternalMapQueryContext;
+import net.openhft.chronicle.map.MapEntry;
+import net.openhft.chronicle.map.MapSegmentContext;
+import net.openhft.chronicle.map.VanillaChronicleMap;
+
+class ChronicleMapStore<K, V> implements ChronicleMap<KeyWrapper<K>, TimedValue<V>> {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  private final ChronicleMap<KeyWrapper<K>, TimedValue<V>> store;
+  private final ChronicleMapCacheConfig config;
+  private final ChronicleMapStoreMetrics metrics;
+
+  ChronicleMapStore(
+      ChronicleMap<KeyWrapper<K>, TimedValue<V>> store,
+      ChronicleMapCacheConfig config,
+      MetricMaker metricMaker) {
+
+    this.store = store;
+    this.config = config;
+    this.metrics = new ChronicleMapStoreMetrics(store.name(), metricMaker);
+    metrics.registerCallBackMetrics(this);
+  }
+
+  /**
+   * Attempt to put the key/value pair into the chronicle-map store. Also catches and warns on disk
+   * allocation errors, so that such failures result in non-cached entries rather than throwing.
+   *
+   * @param wrappedKey the wrapped key value
+   * @param timedVal the timed value
+   * @return true when the value was successfully inserted in chronicle-map, false otherwise
+   */
+  public boolean tryPut(KeyWrapper<K> wrappedKey, TimedValue<V> timedVal) {
+    try {
+      store.put(wrappedKey, timedVal);
+    } catch (IllegalArgumentException | IllegalStateException e) {
+      metrics.incrementPutFailures();
+      logger.atWarning().withCause(e).log(
+          "[cache %s] Caught exception when inserting entry '%s' in chronicle-map",
+          store.name(), wrappedKey.getValue());
+      return false;
+    }
+    return true;
+  }
+
+  @SuppressWarnings("rawtypes")
+  public double percentageUsedAutoResizes() {
+    /*
+     * Chronicle-map already exposes the number of _remaining_ auto-resizes, but
+     * this is an absolute value, and it is not enough to understand the
+     * percentage of auto-resizes that have been utilized.
+     *
+     * For that, we fist need to understand the _maximum_ number of possible
+     * resizes (inclusive of the resizes allowed by the max-bloat factor).
+     * This information is exposed at low level, by the VanillaChronicleMap,
+     * which has access to the number of allocated segments.
+     *
+     * So we proceed as follows:
+     *
+     * Calculate the maximum number of segments by multiplying the allocated
+     * segments (`actualSegments`) by the configured max-bloat-factor.
+     *
+     * The ratio between this value and the _current_ segment utilization
+     * (`getExtraTiersInUse`) shows the overall percentage.
+     */
+    VanillaChronicleMap vanillaStore = (VanillaChronicleMap) store;
+    long usedResizes = vanillaStore.globalMutableState().getExtraTiersInUse();
+    return usedResizes * 100 / maxAutoResizes();
+  }
+
+  @SuppressWarnings("rawtypes")
+  public double maxAutoResizes() {
+    return config.getMaxBloatFactor() * ((VanillaChronicleMap) store).actualSegments;
+  }
+
+  @Override
+  public int size() {
+    return store.size();
+  }
+
+  @Override
+  public boolean isEmpty() {
+    return store.isEmpty();
+  }
+
+  @Override
+  public boolean containsKey(Object key) {
+    return store.containsKey(key);
+  }
+
+  @Override
+  public boolean containsValue(Object value) {
+    return store.containsValue(value);
+  }
+
+  @Override
+  public TimedValue<V> get(Object key) {
+    return store.get(key);
+  }
+
+  @Override
+  public TimedValue<V> put(KeyWrapper<K> key, TimedValue<V> value) {
+    return store.put(key, value);
+  }
+
+  @Override
+  public TimedValue<V> remove(Object key) {
+    return store.remove(key);
+  }
+
+  @Override
+  public void putAll(Map<? extends KeyWrapper<K>, ? extends TimedValue<V>> m) {
+    store.putAll(m);
+  }
+
+  @Override
+  public void clear() {
+    store.clear();
+  }
+
+  @Override
+  public Set<KeyWrapper<K>> keySet() {
+    return store.keySet();
+  }
+
+  @Override
+  public Collection<TimedValue<V>> values() {
+    return store.values();
+  }
+
+  @Override
+  public Set<Entry<KeyWrapper<K>, TimedValue<V>>> entrySet() {
+    return store.entrySet();
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    return store.equals(o);
+  }
+
+  @Override
+  public int hashCode() {
+    return store.hashCode();
+  }
+
+  @Override
+  public TimedValue<V> getUsing(KeyWrapper<K> key, TimedValue<V> usingValue) {
+    return store.getUsing(key, usingValue);
+  }
+
+  @Override
+  public TimedValue<V> acquireUsing(KeyWrapper<K> key, TimedValue<V> usingValue) {
+    return store.acquireUsing(key, usingValue);
+  }
+
+  @Override
+  public Closeable acquireContext(KeyWrapper<K> key, TimedValue<V> usingValue) {
+    return store.acquireContext(key, usingValue);
+  }
+
+  @Override
+  public <R> R getMapped(
+      KeyWrapper<K> key, SerializableFunction<? super TimedValue<V>, R> function) {
+    return store.getMapped(key, function);
+  }
+
+  @Override
+  public void getAll(File toFile) throws IOException {
+    store.getAll(toFile);
+  }
+
+  @Override
+  public void putAll(File fromFile) throws IOException {
+    store.putAll(fromFile);
+  }
+
+  @Override
+  public Class<TimedValue<V>> valueClass() {
+    return store.valueClass();
+  }
+
+  @Override
+  public Type valueType() {
+    return store.valueType();
+  }
+
+  @Override
+  public short percentageFreeSpace() {
+    return store.percentageFreeSpace();
+  }
+
+  @Override
+  public int remainingAutoResizes() {
+    return store.remainingAutoResizes();
+  }
+
+  @Override
+  public TimedValue<V> putIfAbsent(KeyWrapper<K> key, TimedValue<V> value) {
+    return store.putIfAbsent(key, value);
+  }
+
+  @Override
+  public boolean remove(Object key, Object value) {
+    return store.remove(key, value);
+  }
+
+  @Override
+  public boolean replace(KeyWrapper<K> key, TimedValue<V> oldValue, TimedValue<V> newValue) {
+    return store.replace(key, oldValue, newValue);
+  }
+
+  @Override
+  public TimedValue<V> replace(KeyWrapper<K> key, TimedValue<V> value) {
+    return store.replace(key, value);
+  }
+
+  @Override
+  public File file() {
+    return store.file();
+  }
+
+  @Override
+  public String name() {
+    return store.name();
+  }
+
+  @Override
+  public String toIdentityString() {
+    return store.toIdentityString();
+  }
+
+  @Override
+  public long longSize() {
+    return store.longSize();
+  }
+
+  @Override
+  public long offHeapMemoryUsed() {
+    return store.offHeapMemoryUsed();
+  }
+
+  @Override
+  public Class<KeyWrapper<K>> keyClass() {
+    return store.keyClass();
+  }
+
+  @Override
+  public Type keyType() {
+    return store.keyType();
+  }
+
+  @Override
+  public ExternalMapQueryContext<KeyWrapper<K>, TimedValue<V>, ?> queryContext(KeyWrapper<K> key) {
+    return store.queryContext(key);
+  }
+
+  @Override
+  public ExternalMapQueryContext<KeyWrapper<K>, TimedValue<V>, ?> queryContext(
+      Data<KeyWrapper<K>> key) {
+    return store.queryContext(key);
+  }
+
+  @Override
+  public ExternalMapQueryContext<KeyWrapper<K>, TimedValue<V>, ?> queryContext(
+      @SuppressWarnings("rawtypes") BytesStore keyBytes, long offset, long size) {
+    return store.queryContext(keyBytes, offset, size);
+  }
+
+  @Override
+  public MapSegmentContext<KeyWrapper<K>, TimedValue<V>, ?> segmentContext(int segmentIndex) {
+    return store.segmentContext(segmentIndex);
+  }
+
+  @Override
+  public int segments() {
+    return store.segments();
+  }
+
+  @Override
+  public boolean forEachEntryWhile(
+      Predicate<? super MapEntry<KeyWrapper<K>, TimedValue<V>>> predicate) {
+    return store.forEachEntryWhile(predicate);
+  }
+
+  @Override
+  public void forEachEntry(Consumer<? super MapEntry<KeyWrapper<K>, TimedValue<V>>> action) {
+    store.forEachEntry(action);
+  }
+
+  @Override
+  public void close() {
+    store.close();
+  }
+
+  @Override
+  public boolean isOpen() {
+    return store.isOpen();
+  }
+}
diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStoreMetrics.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStoreMetrics.java
new file mode 100644
index 0000000..cf758b5
--- /dev/null
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapStoreMetrics.java
@@ -0,0 +1,76 @@
+// Copyright (C) 2022 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.googlesource.gerrit.modules.cache.chroniclemap;
+
+import com.google.gerrit.metrics.Counter0;
+import com.google.gerrit.metrics.Description;
+import com.google.gerrit.metrics.MetricMaker;
+
+class ChronicleMapStoreMetrics {
+  private final String sanitizedName;
+  private final MetricMaker metricMaker;
+  private final String name;
+  private final Counter0 storePutFailures;
+
+  ChronicleMapStoreMetrics(String name, MetricMaker metricMaker) {
+    this.name = name;
+    this.sanitizedName = metricMaker.sanitizeMetricName(name);
+    this.metricMaker = metricMaker;
+
+    this.storePutFailures =
+        metricMaker.newCounter(
+            "cache/chroniclemap/store_put_failures_" + sanitizedName,
+            new Description(
+                    "The number of errors caught when inserting entries in chronicle-map store: "
+                        + name)
+                .setCumulative()
+                .setUnit("errors"));
+  }
+
+  void incrementPutFailures() {
+    storePutFailures.increment();
+  }
+
+  <K, V> void registerCallBackMetrics(ChronicleMapStore<K, V> store) {
+    String PERCENTAGE_FREE_SPACE_METRIC =
+        "cache/chroniclemap/percentage_free_space_" + sanitizedName;
+    String REMAINING_AUTORESIZES_METRIC =
+        "cache/chroniclemap/remaining_autoresizes_" + sanitizedName;
+    String MAX_AUTORESIZES_METRIC = "cache/chroniclemap/max_autoresizes_" + sanitizedName;
+
+    metricMaker.newCallbackMetric(
+        PERCENTAGE_FREE_SPACE_METRIC,
+        Long.class,
+        new Description(
+            String.format("The amount of free space in the %s cache as a percentage", name)),
+        () -> (long) store.percentageFreeSpace());
+
+    metricMaker.newCallbackMetric(
+        REMAINING_AUTORESIZES_METRIC,
+        Integer.class,
+        new Description(
+            String.format(
+                "The number of times the %s cache can automatically expand its capacity", name)),
+        store::remainingAutoResizes);
+
+    metricMaker.newConstantMetric(
+        MAX_AUTORESIZES_METRIC,
+        store.maxAutoResizes(),
+        new Description(
+            String.format(
+                "The maximum number of times the %s cache can automatically expand its capacity",
+                name)));
+  }
+}
diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index 7e23698..652b328 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -14,8 +14,8 @@
 git clone https://gerrit.googlesource.com/gerrit
 git clone https://gerrit.googlesource.com/modules/cache-chroniclemap
 cd gerrit/plugins
-ln -s ../../cache-chroniclemap cache-chroniclemap
-ln -sf ../../external_plugin_deps.bzl .
+ln -s ../../cache-chroniclemap .
+ln -sf ../../cache-chroniclemap/external_plugin_deps.bzl .
 ```
 
 From the Gerrit source tree issue the command `bazelsk build plugins/cache-chroniclemap`.
diff --git a/src/main/resources/Documentation/metrics.md b/src/main/resources/Documentation/metrics.md
index 8e176ef..2928708 100644
--- a/src/main/resources/Documentation/metrics.md
+++ b/src/main/resources/Documentation/metrics.md
@@ -17,8 +17,14 @@
   See the [official documentation](https://javadoc.io/static/net.openhft/chronicle-map/3.20.83/net/openhft/chronicle/map/ChronicleMap.html#remainingAutoResizes--)
   for more information.
 
+* cache/chroniclemap/max_autoresizes_<cache-name>
+  : The maximum number of times the cache can automatically expand its capacity.
+
 * cache/chroniclemap/hot_keys_capacity_<cache-name>
   : Constant number of hot keys for the cache that can be kept in memory.
 
 * cache/chroniclemap/hot_keys_size_<cache-name>
-  : The number of hot keys for the cache that are currently in memory.
\ No newline at end of file
+  : The number of hot keys for the cache that are currently in memory.
+
+* "cache/chroniclemap/store_put_failures_<cache-name>
+  : The number of errors caught when inserting entries in chronicle-map store
\ No newline at end of file
diff --git a/src/main/resources/Documentation/tuning.md b/src/main/resources/Documentation/tuning.md
index feb98fc..77078a4 100644
--- a/src/main/resources/Documentation/tuning.md
+++ b/src/main/resources/Documentation/tuning.md
@@ -12,7 +12,7 @@
 to analyze your existing H2 caches [here](#analyze-h2-caches).
 
 In case you have already migrated to chronicle-map please follow instructions on
-how to further tune existing .dat caches [here](#tune-chronicle-map-caches).
+how to further tune existing .dat caches [here](#auto-adjust-chronicle-map-caches).
 
 ## Analyze H2 caches
 
@@ -148,7 +148,7 @@
 * You can now run an the tuning command:
 
 ```bash
-ssh -p 29418 admin@<gerrit-server> cache-chroniclemap auto-adjust-caches [--dry-run]
+ssh -p 29418 admin@<gerrit-server> cache-chroniclemap auto-adjust-caches [--dry-run] [cache-name]
 ```
 
 * You can also use the REST-API:
@@ -162,6 +162,28 @@
 Calculate the average key and value size, but do not migrate current cache
 data into new files
 
+* `--max-entries` or `-m` (SSH), `?max-entries` or `?m` (REST-API) optional parameter
+
+The number of entries the tuned cache file is going to hold. This is typically
+useful when the auto-tuning is executed with the intent to increase the number
+of entries that the current cache can hold. When not specified, the
+auto-adjust-cache command checks the percentage utilization of the current
+cache.
+
+If the current utilization of the cache is higher than 50%, then `maxEntries`
+for the tuned cache will be increased by a factor of *2*.
+
+To _decrease_ the number of max entries during auto-tuning, the `max-entries`
+value should be passed _explicitly_.
+
+Note that this parameter will be used globally across all caches, so if you want
+to increase the size of a particular cache only you should be using this
+together with the `cache-name` parameter.
+
+* `cache-name` (SSH), `?CACHE_NAME=cache-name` (REST-API) optional restriction of the caches
+  to analyze and auto-tune. The parameter can be repeated multiple times for analyzing
+  multiple caches. By default, analyze and adjust all persistent caches.
+
 For each chronicle-map cache that needs tuning (i.e. `foo_1.dat` file) in
 the `cache` directory, a new one will be created (i.e. `foo_1_tuned_<timestamp>.dat`).
 The new cache will have these characteristics:
diff --git a/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesIT.java b/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesIT.java
index 087e804..776ee45 100644
--- a/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesIT.java
+++ b/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/AutoAdjustCachesIT.java
@@ -15,6 +15,8 @@
 package com.googlesource.gerrit.modules.cache.chroniclemap;
 
 import static com.google.common.truth.Truth.assertThat;
+import static com.googlesource.gerrit.modules.cache.chroniclemap.AutoAdjustCaches.MAX_ENTRIES_MULTIPLIER;
+import static com.googlesource.gerrit.modules.cache.chroniclemap.AutoAdjustCaches.PERCENTAGE_SIZE_INCREASE_THRESHOLD;
 import static com.googlesource.gerrit.modules.cache.chroniclemap.AutoAdjustCachesCommand.CONFIG_HEADER;
 import static com.googlesource.gerrit.modules.cache.chroniclemap.AutoAdjustCachesCommand.TUNED_INFIX;
 import static com.googlesource.gerrit.modules.cache.chroniclemap.ChronicleMapCacheConfig.Defaults.maxBloatFactorFor;
@@ -41,6 +43,7 @@
 import java.nio.file.Path;
 import java.util.Objects;
 import java.util.Set;
+import java.util.UUID;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -129,6 +132,43 @@
   }
 
   @Test
+  @GerritConfig(name = "cache.test_cache.maxEntries", value = "10")
+  @GerritConfig(name = "cache.test_cache.maxBloatFactor", value = "1")
+  public void shouldIncreaseCacheSizeWhenIsGettingFull() throws Exception {
+    ChronicleMapCacheImpl<String, String> chronicleMapCache =
+        (ChronicleMapCacheImpl<String, String>) testCache;
+
+    while (chronicleMapCache.percentageUsedAutoResizes() < PERCENTAGE_SIZE_INCREASE_THRESHOLD) {
+      String aString = UUID.randomUUID().toString();
+      testCache.put(aString, aString);
+    }
+
+    String tuneResult = adminSshSession.exec(SSH_CMD + " " + TEST_CACHE_NAME);
+    adminSshSession.assertSuccess();
+
+    Config tunedConfig = configResult(tuneResult, CONFIG_HEADER);
+    assertThat(tunedConfig.getSubsections("cache")).contains(TEST_CACHE_NAME);
+    assertThat(tunedConfig.getLong("cache", TEST_CACHE_NAME, "maxEntries", 0))
+        .isEqualTo(chronicleMapCache.getConfig().getMaxEntries() * MAX_ENTRIES_MULTIPLIER);
+  }
+
+  @Test
+  public void shouldHonourMaxEntriesParameter() throws Exception {
+    createChange();
+    Long wantedMaxEntries = 100L;
+
+    String result =
+        adminSshSession.exec(String.format("%s --max-entries %s", SSH_CMD, wantedMaxEntries));
+
+    adminSshSession.assertSuccess();
+    Config configResult = configResult(result, CONFIG_HEADER);
+
+    for (String cache : EXPECTED_CACHES) {
+      assertThat(configResult.getLong("cache", cache, "maxEntries", 0)).isEqualTo(wantedMaxEntries);
+    }
+  }
+
+  @Test
   public void shouldCreateNewCacheFiles() throws Exception {
     createChange();
 
@@ -142,12 +182,42 @@
   }
 
   @Test
+  public void shouldCreateNewCacheFileForSingleGitFileDiffCache() throws Exception {
+    createChange();
+
+    adminSshSession.exec(SSH_CMD + " " + GIT_FILE_DIFF);
+
+    adminSshSession.assertSuccess();
+    Set<String> tunedCaches =
+        tunedFileNamesSet(n -> n.matches(".*" + AutoAdjustCaches.TUNED_INFIX + ".*"));
+
+    assertThat(tunedCaches.size()).isEqualTo(1);
+  }
+
+  @Test
+  public void shouldCreateNewCacheFileForSingleGerritFileDiffCache() throws Exception {
+    createChange();
+
+    adminSshSession.exec(SSH_CMD + " " + GERRIT_FILE_DIFF);
+
+    adminSshSession.assertSuccess();
+    Set<String> tunedCaches =
+        tunedFileNamesSet(n -> n.matches(".*" + AutoAdjustCaches.TUNED_INFIX + ".*"));
+
+    assertThat(tunedCaches.size()).isEqualTo(1);
+  }
+
+  @Test
   @GerritConfig(name = "cache.test_cache.avgKeySize", value = "207")
   @GerritConfig(name = "cache.test_cache.avgValueSize", value = "207")
   public void shouldNotRecreateTestCacheFileWhenAlreadyTuned() throws Exception {
     testCache.get(TEST_CACHE_KEY_100_CHARS);
 
-    String tuneResult = adminSshSession.exec(SSH_CMD);
+    String tuneResult =
+        adminSshSession.exec(
+            String.format(
+                "%s --max-entries %s",
+                SSH_CMD, ChronicleMapCacheConfig.Defaults.maxEntriesFor(TEST_CACHE_KEY_100_CHARS)));
     adminSshSession.assertSuccess();
 
     assertThat(configResult(tuneResult, CONFIG_HEADER).getSubsections("cache"))
@@ -190,6 +260,47 @@
     assertThat(tunedFileNamesSet(MATCH_ALL)).isNotEmpty();
   }
 
+  @Test
+  public void shouldHonourMaxEntriesOverRestForAdmin() throws Exception {
+    Long wantedMaxEntries = 100L;
+
+    RestResponse resp =
+        adminRestSession.put(String.format("%s?max-entries=%s", REST_CMD, wantedMaxEntries));
+
+    resp.assertCreated();
+
+    assertThat(
+            configResult(resp.getEntityContent(), null)
+                .getLong("cache", ACCOUNTS, "maxEntries", 0L))
+        .isEqualTo(wantedMaxEntries);
+  }
+
+  @Test
+  public void shouldAllowTuningOfSingleGitFileDiffCacheOverRestForAdmin() throws Exception {
+    createChange();
+
+    RestResponse resp = adminRestSession.put(REST_CMD + "?CACHE_NAME=" + GIT_FILE_DIFF);
+
+    resp.assertCreated();
+
+    assertThat(configResult(resp.getEntityContent(), null).getSubsections("cache")).isNotEmpty();
+    assertThat(tunedFileNamesSet(n -> n.matches(".*" + AutoAdjustCaches.TUNED_INFIX + ".*")))
+        .hasSize(1);
+  }
+
+  @Test
+  public void shouldAllowTuningOfSingleGerritFileDiffCacheOverRestForAdmin() throws Exception {
+    createChange();
+
+    RestResponse resp = adminRestSession.put(REST_CMD + "?CACHE_NAME=" + GERRIT_FILE_DIFF);
+
+    resp.assertCreated();
+
+    assertThat(configResult(resp.getEntityContent(), null).getSubsections("cache")).isNotEmpty();
+    assertThat(tunedFileNamesSet(n -> n.matches(".*" + AutoAdjustCaches.TUNED_INFIX + ".*")))
+        .hasSize(1);
+  }
+
   private Config configResult(String result, @Nullable String configHeader)
       throws ConfigInvalidException {
     Config configResult = new Config();
diff --git a/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheTest.java b/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheTest.java
index 91ddbe3..0041c53 100644
--- a/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheTest.java
+++ b/src/test/java/com/googlesource/gerrit/modules/cache/chroniclemap/ChronicleMapCacheTest.java
@@ -17,6 +17,7 @@
 import static com.google.common.truth.Truth.assertWithMessage;
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
+import com.codahale.metrics.Counter;
 import com.codahale.metrics.Gauge;
 import com.codahale.metrics.MetricRegistry;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
@@ -355,11 +356,50 @@
     while (!cache.runningOutOfFreeSpace()) {
       cache.put(UUID.randomUUID().toString(), UUID.randomUUID().toString());
     }
-    assertThat(cache.runningOutOfFreeSpace()).isTrue();
+  }
 
-    cache.prune();
+  @Test
+  public void shouldRecoverWhenPutFailsBecauseEntryIsTooBig() throws Exception {
+    String key = UUID.randomUUID().toString();
+    String value = UUID.randomUUID().toString();
+    int uuidSize = valueSize(value);
+    gerritConfig.setInt("cache", testCacheName, "maxEntries", 1);
+    gerritConfig.setInt("cache", testCacheName, "maxBloatFactor", 1);
+    gerritConfig.setInt("cache", testCacheName, "avgKeySize", uuidSize / 2);
+    gerritConfig.setInt("cache", testCacheName, "avgValueSize", uuidSize / 2);
+    gerritConfig.save();
 
-    assertThat(cache.runningOutOfFreeSpace()).isFalse();
+    ChronicleMapCacheImpl<String, String> cache = newCacheWithMetrics(testCacheName, value);
+
+    cache.put(key, value);
+
+    assertThat(cache.getStore().size()).isEqualTo(0);
+    assertThat(cache.getIfPresent(key)).isNull();
+    assertThat(getCounter("cache/chroniclemap/store_put_failures_" + testCacheName).getCount())
+        .isEqualTo(1L);
+  }
+
+  @Test
+  public void shouldRecoverWhenPutFailsBecauseCacheCannotExpand() throws Exception {
+    String key = UUID.randomUUID().toString();
+    String value = UUID.randomUUID().toString();
+    int uuidSize = valueSize(value);
+    gerritConfig.setInt("cache", testCacheName, "maxEntries", 1);
+    gerritConfig.setInt("cache", testCacheName, "maxBloatFactor", 1);
+    gerritConfig.setInt("cache", testCacheName, "avgKeySize", uuidSize);
+    gerritConfig.setInt("cache", testCacheName, "avgValueSize", uuidSize);
+    gerritConfig.save();
+
+    ChronicleMapCacheImpl<String, String> cache = newCacheWithoutLoader();
+
+    cache.put(UUID.randomUUID().toString(), UUID.randomUUID().toString());
+    cache.put(UUID.randomUUID().toString(), UUID.randomUUID().toString());
+    cache.put(key, value);
+
+    assertThat(cache.getStore().size()).isEqualTo(2);
+    assertThat(cache.getIfPresent(key)).isNull();
+    assertThat(getCounter("cache/chroniclemap/store_put_failures_" + testCacheName).getCount())
+        .isEqualTo(1L);
   }
 
   @Test
@@ -403,6 +443,21 @@
   }
 
   @Test
+  public void shouldTriggerMaxAutoResizeMetric() throws Exception {
+    String cachedValue = UUID.randomUUID().toString();
+    String maxAutoResizeMetricName = "cache/chroniclemap/max_autoresizes_" + testCacheName;
+    gerritConfig.setInt("cache", testCacheName, "maxEntries", 2);
+    gerritConfig.setInt("cache", testCacheName, "avgKeySize", cachedValue.getBytes().length);
+    gerritConfig.setInt("cache", testCacheName, "avgValueSize", valueSize(cachedValue));
+    gerritConfig.setInt("cache", testCacheName, "maxBloatFactor", 3);
+    gerritConfig.save();
+
+    newCacheWithMetrics(testCacheName, cachedValue);
+
+    assertThat(getMetric(maxAutoResizeMetricName).getValue()).isEqualTo(3);
+  }
+
+  @Test
   public void shouldTriggerHotKeysCapacityCacheMetric() throws Exception {
     String cachedValue = UUID.randomUUID().toString();
     int percentageHotKeys = 60;
@@ -487,6 +542,7 @@
     String hotKeySizeMetricName = "cache/chroniclemap/hot_keys_size_" + sanitized;
     String percentageFreeMetricName = "cache/chroniclemap/percentage_free_space_" + sanitized;
     String autoResizeMetricName = "cache/chroniclemap/remaining_autoresizes_" + sanitized;
+    String maxAutoResizeMetricName = "cache/chroniclemap/max_autoresizes_" + sanitized;
     String hotKeyCapacityMetricName = "cache/chroniclemap/hot_keys_capacity_" + sanitized;
 
     newCacheWithMetrics(cacheName, null);
@@ -494,6 +550,7 @@
     getMetric(hotKeySizeMetricName);
     getMetric(percentageFreeMetricName);
     getMetric(autoResizeMetricName);
+    getMetric(maxAutoResizeMetricName);
     getMetric(hotKeyCapacityMetricName);
   }
 
@@ -591,4 +648,10 @@
     assertWithMessage(name).that(gauge).isNotNull();
     return gauge;
   }
+
+  private Counter getCounter(String name) {
+    Counter counter = (Counter) metricRegistry.getMetrics().get(name);
+    assertWithMessage(name).that(counter).isNotNull();
+    return counter;
+  }
 }