From 9602869d19a323cdb9396cb52ba9bd818d21a7a9 Mon Sep 17 00:00:00 2001 From: Tsz-wo Sze Date: Sat, 30 Mar 2013 23:57:27 +0000 Subject: [PATCH] HDFS-4648. For snapshot deletion, when merging the diff from to-delete snapshot to the prior snapshot, make sure files/directories created after the prior snapshot get deleted. Contributed by Jing Zhao git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/HDFS-2802@1462865 13f79535-47bb-0310-9956-ffa450edef68 --- .../hadoop-hdfs/CHANGES.HDFS-2802.txt | 4 ++ .../hdfs/server/namenode/INodeDirectory.java | 2 +- .../snapshot/INodeDirectoryWithSnapshot.java | 62 ++++++++++++++++- .../namenode/TestFSImageWithSnapshot.java | 66 ++++++++++++++++++- .../snapshot/TestSnapshotDeletion.java | 51 ++++++++++++++ 5 files changed, 180 insertions(+), 5 deletions(-) diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-2802.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-2802.txt index d098d4686fa..2b9379d888d 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-2802.txt +++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-2802.txt @@ -216,3 +216,7 @@ Branch-2802 Snapshot (Unreleased) HDFS-4636. Update quota usage when deleting files/dirs that were created after taking the latest snapshot. (Jing Zhao via szetszwo) + + HDFS-4648. For snapshot deletion, when merging the diff from to-delete + snapshot to the prior snapshot, make sure files/directories created after + the prior snapshot get deleted. (Jing Zhao via szetszwo) diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeDirectory.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeDirectory.java index b0a4be2bc0c..d9c9c916bf4 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeDirectory.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeDirectory.java @@ -622,7 +622,7 @@ public class INodeDirectory extends INodeWithAdditionalFields { // the diff list, the snapshot to be deleted has been combined or renamed // to its latest previous snapshot. (besides, we also need to consider nodes // created after prior but before snapshot. this will be done in - // INodeDirectoryWithSnapshot#cleanSubtree + // INodeDirectoryWithSnapshot#cleanSubtree) Snapshot s = snapshot != null && prior != null ? prior : snapshot; for (INode child : getChildrenList(s)) { Quota.Counts childCounts = child.cleanSubtree(snapshot, prior, diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectoryWithSnapshot.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectoryWithSnapshot.java index 86964a0da9d..e56dd4dd8aa 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectoryWithSnapshot.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectoryWithSnapshot.java @@ -19,8 +19,10 @@ package org.apache.hadoop.hdfs.server.namenode.snapshot; import java.io.DataOutputStream; import java.io.IOException; +import java.util.ArrayDeque; import java.util.ArrayList; import java.util.Collections; +import java.util.Deque; import java.util.Iterator; import java.util.List; import java.util.Map; @@ -674,9 +676,27 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota { if (prior != null) { DirectoryDiff priorDiff = this.getDiffs().getDiff(prior); if (priorDiff != null) { - for (INode cNode : priorDiff.getChildrenDiff().getList(ListType.CREATED)) { + // For files/directories created between "prior" and "snapshot", + // we need to clear snapshot copies for "snapshot". Note that we must + // use null as prior in the cleanSubtree call. Files/directories that + // were created before "prior" will be covered by the later + // cleanSubtreeRecursively call. + for (INode cNode : priorDiff.getChildrenDiff().getList( + ListType.CREATED)) { counts.add(cNode.cleanSubtree(snapshot, null, collectedBlocks)); } + // When a directory is moved from the deleted list of the posterior + // diff to the deleted list of this diff, we need to destroy its + // descendants that were 1) created after taking this diff and 2) + // deleted after taking posterior diff. + + // For files moved from posterior's deleted list, we also need to + // delete its snapshot copy associated with the posterior snapshot. + for (INode dNode : priorDiff.getChildrenDiff().getList( + ListType.DELETED)) { + counts.add(cleanDeletedINode(dNode, snapshot, prior, + collectedBlocks)); + } } } } @@ -688,6 +708,46 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota { } return counts; } + + /** + * Clean an inode while we move it from the deleted list of post to the + * deleted list of prior. + * @param inode The inode to clean. + * @param post The post snapshot. + * @param prior The prior snapshot. + * @param collectedBlocks Used to collect blocks for later deletion. + * @return Quota usage update. + */ + private Quota.Counts cleanDeletedINode(INode inode, Snapshot post, + Snapshot prior, final BlocksMapUpdateInfo collectedBlocks) { + Quota.Counts counts = Quota.Counts.newInstance(); + Deque queue = new ArrayDeque(); + queue.addLast(inode); + while (!queue.isEmpty()) { + INode topNode = queue.pollFirst(); + if (topNode instanceof FileWithSnapshot) { + FileWithSnapshot fs = (FileWithSnapshot) topNode; + counts.add(fs.getDiffs().deleteSnapshotDiff(post, prior, + topNode.asFile(), collectedBlocks)); + } else if (topNode.isDirectory()) { + INodeDirectory dir = topNode.asDirectory(); + if (dir instanceof INodeDirectoryWithSnapshot) { + // delete files/dirs created after prior. Note that these + // files/dirs, along with inode, were deleted right after post. + INodeDirectoryWithSnapshot sdir = (INodeDirectoryWithSnapshot) dir; + DirectoryDiff priorDiff = sdir.getDiffs().getDiff(prior); + if (priorDiff != null) { + counts.add(priorDiff.diff.destroyCreatedList(sdir, + collectedBlocks)); + } + } + for (INode child : dir.getChildrenList(prior)) { + queue.addLast(child); + } + } + } + return counts; + } @Override public void destroyAndCollectBlocks( diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSImageWithSnapshot.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSImageWithSnapshot.java index 5d22836b6c5..5b8c63e11aa 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSImageWithSnapshot.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSImageWithSnapshot.java @@ -322,11 +322,9 @@ public class TestFSImageWithSnapshot { DFSTestUtil.createFile(hdfs, sub1file1, BLOCKSIZE, REPLICATION, seed); DFSTestUtil.createFile(hdfs, sub1file2, BLOCKSIZE, REPLICATION, seed); - // 1. create snapshot s0 hdfs.allowSnapshot(dir.toString()); hdfs.createSnapshot(dir, "s0"); - // 2. create snapshot s1 before appending sub1file1 finishes HdfsDataOutputStream out = appendFileWithoutClosing(sub1file1, BLOCKSIZE); out.hsync(EnumSet.of(SyncFlag.UPDATE_LENGTH)); @@ -347,7 +345,7 @@ public class TestFSImageWithSnapshot { * Test fsimage loading when 1) there is an empty file loaded from fsimage, * and 2) there is later an append operation to be applied from edit log. */ - @Test + @Test (timeout=60000) public void testLoadImageWithEmptyFile() throws Exception { // create an empty file Path file = new Path(dir, "file"); @@ -374,4 +372,66 @@ public class TestFSImageWithSnapshot { FileStatus status = hdfs.getFileStatus(file); assertEquals(1, status.getLen()); } + + /** + * Testing a special case with snapshots. When the following steps happen: + * 
+   * 1. Take snapshot s1 on dir.
+   * 2. Create new dir and files under subsubDir, which is descendant of dir.
+   * 3. Take snapshot s2 on dir.
+   * 4. Delete subsubDir.
+   * 5. Delete snapshot s2.
+   *
+ * When we merge the diff from s2 to s1 (since we deleted s2), we need to make + * sure all the files/dirs created after s1 should be destroyed. Otherwise + * we may save these files/dirs to the fsimage, and cause FileNotFound + * Exception while loading fsimage. + */ + @Test (timeout=300000) + public void testSaveLoadImageAfterSnapshotDeletion() + throws Exception { + // create initial dir and subdir + Path dir = new Path("/dir"); + Path subDir = new Path(dir, "subdir"); + Path subsubDir = new Path(subDir, "subsubdir"); + hdfs.mkdirs(subsubDir); + + // take snapshots on subdir and dir + SnapshotTestHelper.createSnapshot(hdfs, dir, "s1"); + + // create new dir under initial dir + Path newDir = new Path(subsubDir, "newdir"); + Path newFile = new Path(newDir, "newfile"); + hdfs.mkdirs(newDir); + DFSTestUtil.createFile(hdfs, newFile, BLOCKSIZE, REPLICATION, seed); + + // create another snapshot + SnapshotTestHelper.createSnapshot(hdfs, dir, "s2"); + + // delete subsubdir + hdfs.delete(subsubDir, true); + + // delete snapshot s2 + hdfs.deleteSnapshot(dir, "s2"); + + // restart cluster + cluster.shutdown(); + cluster = new MiniDFSCluster.Builder(conf).numDataNodes(REPLICATION) + .format(false).build(); + cluster.waitActive(); + fsn = cluster.getNamesystem(); + hdfs = cluster.getFileSystem(); + + // save namespace to fsimage + hdfs.setSafeMode(SafeModeAction.SAFEMODE_ENTER); + hdfs.saveNamespace(); + hdfs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE); + + cluster.shutdown(); + cluster = new MiniDFSCluster.Builder(conf).format(false) + .numDataNodes(REPLICATION).build(); + cluster.waitActive(); + fsn = cluster.getNamesystem(); + hdfs = cluster.getFileSystem(); + } } \ No newline at end of file diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestSnapshotDeletion.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestSnapshotDeletion.java index b9f3a7c95ab..73e65b1567b 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestSnapshotDeletion.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestSnapshotDeletion.java @@ -524,6 +524,57 @@ public class TestSnapshotDeletion { testCombineSnapshotDiffImpl(sub, "subsub1/subsubsub1/", 3); } + /** + * When combine two snapshots, make sure files/directories created after the + * prior snapshot get destroyed. + */ + @Test (timeout=300000) + public void testCombineSnapshotDiff3() throws Exception { + // create initial dir and subdir + Path dir = new Path("/dir"); + Path subDir1 = new Path(dir, "subdir1"); + Path subDir2 = new Path(dir, "subdir2"); + hdfs.mkdirs(subDir2); + Path subsubDir = new Path(subDir1, "subsubdir"); + hdfs.mkdirs(subsubDir); + + // take snapshots on subdir and dir + SnapshotTestHelper.createSnapshot(hdfs, dir, "s1"); + + // create new dir under initial dir + Path newDir = new Path(subsubDir, "newdir"); + Path newFile = new Path(newDir, "newfile"); + DFSTestUtil.createFile(hdfs, newFile, BLOCKSIZE, REPLICATION, seed); + Path newFile2 = new Path(subDir2, "newfile"); + DFSTestUtil.createFile(hdfs, newFile2, BLOCKSIZE, REPLICATION, seed); + + // create another snapshot + SnapshotTestHelper.createSnapshot(hdfs, dir, "s2"); + + checkQuotaUsageComputation(dir, 11, BLOCKSIZE * 2 * REPLICATION); + + // delete subsubdir and subDir2 + hdfs.delete(subsubDir, true); + hdfs.delete(subDir2, true); + + // add diff of s2 to subDir1, subsubDir, and subDir2 + checkQuotaUsageComputation(dir, 14, BLOCKSIZE * 2 * REPLICATION); + + // delete snapshot s2 + hdfs.deleteSnapshot(dir, "s2"); + + // delete s2 diff in dir, subDir2, and subsubDir. Delete newFile, newDir, + // and newFile2. Rename s2 diff to s1 for subDir1 + checkQuotaUsageComputation(dir, 8, 0); + // Check rename of snapshot diff in subDir1 + Path subdir1_s1 = SnapshotTestHelper.getSnapshotPath(dir, "s1", + subDir1.getName()); + Path subdir1_s2 = SnapshotTestHelper.getSnapshotPath(dir, "s2", + subDir1.getName()); + assertTrue(hdfs.exists(subdir1_s1)); + assertFalse(hdfs.exists(subdir1_s2)); + } + /** * Test snapshot deletion * @param snapshotRoot The dir where the snapshots are created