GC: Remove empty references folders After packaging references, the folders containing these references are not deleted. In a busy repository, this causes operations to slow down as traversing the references tree becomes longer. Delete empty reference folders after the loose references have been packed. To avoid deleting a folder that was just created by another concurrent operation, only delete folders that were not modified in the last 30 seconds. Signed-off-by: Hector Oswaldo Caballero <hector.caballero@ericsson.com> Change-Id: Ie79447d6121271cf5e25171be377ea396c7028e0 Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com> Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcDeleteEmptyRefsFoldersTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcDeleteEmptyRefsFoldersTest.java new file mode 100644 index 0000000..76e1534 --- /dev/null +++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcDeleteEmptyRefsFoldersTest.java
@@ -0,0 +1,118 @@ +/* + * Copyright (C) 2018 Ericsson + * and other copyright owners as documented in the project's IP log. + * + * This program and the accompanying materials are made available + * under the terms of the Eclipse Distribution License v1.0 which + * accompanies this distribution, is reproduced below, and is + * available at http://www.eclipse.org/org/documents/edl-v10.php + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * - Neither the name of the Eclipse Foundation, Inc. nor the + * names of its contributors may be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND + * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +package org.eclipse.jgit.internal.storage.file; + +import static org.junit.Assert.assertFalse; +import static org.junit.Assert.assertTrue; + +import java.nio.file.Files; +import java.nio.file.Path; +import java.nio.file.Paths; +import java.nio.file.attribute.FileTime; +import java.time.Instant; + +import org.junit.Before; +import org.junit.Test; + +public class GcDeleteEmptyRefsFoldersTest extends GcTestCase { + private static final String REF_FOLDER_01 = "01"; + private static final String REF_FOLDER_02 = "02"; + + private Path refsDir; + private Path heads; + + @Override + @Before + public void setUp() throws Exception { + super.setUp(); + refsDir = Paths.get(repo.getDirectory().getAbsolutePath()) + .resolve("refs"); + heads = refsDir.resolve("heads"); + } + + @Test + public void emptyRefFoldersAreDeleted() throws Exception { + FileTime fileTime = FileTime.from(Instant.now().minusSeconds(31)); + Path refDir01 = Files.createDirectory(heads.resolve(REF_FOLDER_01)); + Path refDir02 = Files.createDirectory(heads.resolve(REF_FOLDER_02)); + Files.setLastModifiedTime(refDir01, fileTime); + Files.setLastModifiedTime(refDir02, fileTime); + assertTrue(refDir01.toFile().exists()); + assertTrue(refDir02.toFile().exists()); + gc.gc(); + + assertFalse(refDir01.toFile().exists()); + assertFalse(refDir02.toFile().exists()); + } + + @Test + public void emptyRefFoldersAreKeptIfTheyAreTooRecent() + throws Exception { + Path refDir01 = Files.createDirectory(heads.resolve(REF_FOLDER_01)); + Path refDir02 = Files.createDirectory(heads.resolve(REF_FOLDER_02)); + assertTrue(refDir01.toFile().exists()); + assertTrue(refDir02.toFile().exists()); + gc.gc(); + + assertTrue(refDir01.toFile().exists()); + assertTrue(refDir02.toFile().exists()); + } + + @Test + public void nonEmptyRefsFoldersAreKept() throws Exception { + Path refDir01 = Files.createDirectory(heads.resolve(REF_FOLDER_01)); + Path refDir02 = Files.createDirectory(heads.resolve(REF_FOLDER_02)); + Path ref01 = Files.createFile(refDir01.resolve("ref01")); + Path ref02 = Files.createFile(refDir01.resolve("ref02")); + assertTrue(refDir01.toFile().exists()); + assertTrue(refDir02.toFile().exists()); + assertTrue(ref01.toFile().exists()); + assertTrue(ref02.toFile().exists()); + gc.gc(); + assertTrue(refDir01.toFile().exists()); + assertTrue(refDir02.toFile().exists()); + assertTrue(ref01.toFile().exists()); + assertTrue(ref02.toFile().exists()); + } +}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java index e1b309d..55d0751 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
@@ -61,6 +61,8 @@ import java.nio.file.StandardCopyOption; import java.text.MessageFormat; import java.text.ParseException; +import java.time.Instant; +import java.time.temporal.ChronoUnit; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; @@ -865,6 +867,7 @@ else if (RefTreeNames.isRefTree(refdb, ref.getName())) throw new IOException(e); } prunePacked(); + deleteEmptyRefsFolders(); deleteOrphans(); lastPackedRefs = refsBefore; @@ -880,6 +883,49 @@ private static boolean isTag(Ref ref) { return ref.getName().startsWith(Constants.R_TAGS); } + private void deleteEmptyRefsFolders() throws IOException { + Path refs = repo.getDirectory().toPath().resolve("refs"); //$NON-NLS-1$ + try (Stream<Path> entries = Files.list(refs)) { + Iterator<Path> iterator = entries.iterator(); + while (iterator.hasNext()) { + try (Stream<Path> s = Files.list(iterator.next())) { + s.forEach(this::deleteDir); + } + } + } + } + + private void deleteDir(Path dir) { + try (Stream<Path> dirs = Files.walk(dir)) { + dirs.filter(this::isDirectory).sorted(Comparator.reverseOrder()) + .forEach(this::delete); + } catch (IOException e) { + LOG.error(e.getMessage(), e); + } + } + + private boolean isDirectory(Path p) { + return p.toFile().isDirectory(); + } + + private boolean delete(Path d) { + try { + // Avoid deleting a folder that was just created so that concurrent + // operations trying to create a reference are not impacted + Instant threshold = Instant.now().minus(30, ChronoUnit.SECONDS); + Instant lastModified = Files.getLastModifiedTime(d).toInstant(); + if (lastModified.isBefore(threshold)) { + // If the folder is not empty, the delete operation will fail + // silently. This is a cheaper alternative to filtering the + // stream in the calling method. + return d.toFile().delete(); + } + } catch (IOException e) { + LOG.error(e.getMessage(), e); + } + return false; + } + /** * Deletes orphans * <p>