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Posted to common-commits@hadoop.apache.org by ar...@apache.org on 2016/01/12 05:32:05 UTC
[06/23] hadoop git commit: HADOOP-12678. Handle empty rename pending
metadata file during atomic rename in redo path. Contributed by Madhumita
Chakraborty.
HADOOP-12678. Handle empty rename pending metadata file during atomic rename in redo path. Contributed by Madhumita Chakraborty.
Project: http://git-wip-us.apache.org/repos/asf/hadoop/repo
Commit: http://git-wip-us.apache.org/repos/asf/hadoop/commit/f0fa6d86
Tree: http://git-wip-us.apache.org/repos/asf/hadoop/tree/f0fa6d86
Diff: http://git-wip-us.apache.org/repos/asf/hadoop/diff/f0fa6d86
Branch: refs/heads/HDFS-1312
Commit: f0fa6d869b9abb5a900ea1c9eb4eb19ec9831dc4
Parents: 109e528
Author: cnauroth <cn...@apache.org>
Authored: Fri Jan 8 20:18:54 2016 -0800
Committer: cnauroth <cn...@apache.org>
Committed: Fri Jan 8 20:18:59 2016 -0800
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hadoop-common-project/hadoop-common/CHANGES.txt | 3 ++
.../hadoop/fs/azure/NativeAzureFileSystem.java | 38 +++++++++++--
.../fs/azure/NativeAzureFileSystemBaseTest.java | 57 ++++++++++++++++++++
3 files changed, 94 insertions(+), 4 deletions(-)
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http://git-wip-us.apache.org/repos/asf/hadoop/blob/f0fa6d86/hadoop-common-project/hadoop-common/CHANGES.txt
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diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 78cd2dd..a5aebeb 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -1571,6 +1571,9 @@ Release 2.8.0 - UNRELEASED
HADOOP-12675. Fix description about retention period in usage of expunge
command. (Masatake Iwasaki via stevel)
+ HADOOP-12678. Handle empty rename pending metadata file during atomic rename
+ in redo path. (Madhumita Chakraborty via cnauroth)
+
Release 2.7.3 - UNRELEASED
INCOMPATIBLE CHANGES
http://git-wip-us.apache.org/repos/asf/hadoop/blob/f0fa6d86/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java
----------------------------------------------------------------------
diff --git a/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java b/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java
index 34791e5..96786aa 100644
--- a/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java
+++ b/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java
@@ -143,9 +143,15 @@ public class NativeAzureFileSystem extends FileSystem {
FSDataInputStream input = fs.open(f);
byte[] bytes = new byte[MAX_RENAME_PENDING_FILE_SIZE];
int l = input.read(bytes);
- if (l < 0) {
- throw new IOException(
- "Error reading pending rename file contents -- no data available");
+ if (l <= 0) {
+ // Jira HADOOP-12678 -Handle empty rename pending metadata file during
+ // atomic rename in redo path. If during renamepending file is created
+ // but not written yet, then this means that rename operation
+ // has not started yet. So we should delete rename pending metadata file.
+ LOG.error("Deleting empty rename pending file "
+ + redoFile + " -- no data available");
+ deleteRenamePendingFile(fs, redoFile);
+ return;
}
if (l == MAX_RENAME_PENDING_FILE_SIZE) {
throw new IOException(
@@ -178,7 +184,7 @@ public class NativeAzureFileSystem extends FileSystem {
redoFile, contents);
// delete the -RenamePending.json file
- fs.delete(redoFile, false);
+ deleteRenamePendingFile(fs, redoFile);
return;
}
@@ -216,6 +222,30 @@ public class NativeAzureFileSystem extends FileSystem {
}
/**
+ * Deletes rename pending metadata file
+ * @param fs -- the file system
+ * @param redoFile - rename pending metadata file path
+ * @throws IOException - If deletion fails
+ */
+ @VisibleForTesting
+ void deleteRenamePendingFile(FileSystem fs, Path redoFile)
+ throws IOException {
+ try {
+ fs.delete(redoFile, false);
+ } catch (IOException e) {
+ // If the rename metadata was not found then somebody probably
+ // raced with us and finished the delete first
+ Throwable t = e.getCause();
+ if (t != null && t instanceof StorageException
+ && "BlobNotFound".equals(((StorageException) t).getErrorCode())) {
+ LOG.warn("rename pending file " + redoFile + " is already deleted");
+ } else {
+ throw e;
+ }
+ }
+ }
+
+ /**
* Write to disk the information needed to redo folder rename,
* in JSON format. The file name will be
* {@code wasb://<sourceFolderPrefix>/folderName-RenamePending.json}
http://git-wip-us.apache.org/repos/asf/hadoop/blob/f0fa6d86/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azure/NativeAzureFileSystemBaseTest.java
----------------------------------------------------------------------
diff --git a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azure/NativeAzureFileSystemBaseTest.java b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azure/NativeAzureFileSystemBaseTest.java
index 1f07677..7837098 100644
--- a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azure/NativeAzureFileSystemBaseTest.java
+++ b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azure/NativeAzureFileSystemBaseTest.java
@@ -846,6 +846,63 @@ public abstract class NativeAzureFileSystemBaseTest {
}
/**
+ * Test the situation when the rename metadata file is empty
+ * i.e. it is created but not written yet. In that case in next rename
+ * this empty file should be deleted. As zero byte metadata file means
+ * rename has not started yet. This is to emulate the scenario where
+ * the process crashes just after creating rename metadata file.
+ * We had a bug (HADOOP-12678) that in that case listing used to fail and
+ * hbase master did not use to come up
+ */
+ @Test
+ public void testRedoRenameFolderInFolderListingWithZeroByteRenameMetadata()
+ throws IOException {
+ // create original folder
+ String parent = "parent";
+ Path parentFolder = new Path(parent);
+ assertTrue(fs.mkdirs(parentFolder));
+ Path inner = new Path(parentFolder, "innerFolder");
+ assertTrue(fs.mkdirs(inner));
+ Path inner2 = new Path(parentFolder, "innerFolder2");
+ assertTrue(fs.mkdirs(inner2));
+ Path innerFile = new Path(inner2, "file");
+ assertTrue(fs.createNewFile(innerFile));
+
+ Path inner2renamed = new Path(parentFolder, "innerFolder2Renamed");
+
+ // Create an empty rename-pending file
+ final String renamePendingStr = inner2 + FolderRenamePending.SUFFIX;
+ Path renamePendingFile = new Path(renamePendingStr);
+ FSDataOutputStream out = fs.create(renamePendingFile, true);
+ assertTrue(out != null);
+ out.close();
+
+ // Redo the rename operation based on the contents of the
+ // -RenamePending.json file. Trigger the redo by listing
+ // the parent folder. It should not throw and it should
+ // delete empty rename pending file
+ FileStatus[] listed = fs.listStatus(parentFolder);
+ assertEquals(2, listed.length);
+ assertTrue(listed[0].isDirectory());
+ assertTrue(listed[1].isDirectory());
+ assertFalse(fs.exists(renamePendingFile));
+
+ // Verify that even if rename pending file is deleted,
+ // deletion should handle that
+ Path home = fs.getHomeDirectory();
+ String relativeHomeDir = getRelativePath(home.toString());
+ NativeAzureFileSystem.FolderRenamePending pending =
+ new NativeAzureFileSystem.FolderRenamePending(
+ relativeHomeDir + "/" + inner2,
+ relativeHomeDir + "/" + inner2renamed, null,
+ (NativeAzureFileSystem) fs);
+ pending.deleteRenamePendingFile(fs, renamePendingFile);
+
+ assertTrue(fs.exists(inner2)); // verify original folder is there
+ assertFalse(fs.exists(inner2renamed)); // verify the target is not there
+ }
+
+ /**
* Test the situation where a rename pending file exists but the rename
* is really done. This could happen if the rename process died just
* before deleting the rename pending file. It exercises a non-standard