HDFS-8883. NameNode Metrics : Add FSNameSystem lock Queue Length. Contributed by Anu Engineer.
(cherry picked from commit a7862d5fe4c505f5d4b0c675438a971733f1f53a) (cherry picked from commit 27ccbd51f6827d4e4a26c2026c024a3400ab96f2) Project: http://git-wip-us.apache.org/repos/asf/hadoop/repo Commit: http://git-wip-us.apache.org/repos/asf/hadoop/commit/e5cb9d9e Tree: http://git-wip-us.apache.org/repos/asf/hadoop/tree/e5cb9d9e Diff: http://git-wip-us.apache.org/repos/asf/hadoop/diff/e5cb9d9e Branch: refs/heads/branch-2.7 Commit: e5cb9d9e186deba933099e5c1906dc3d80efe5c9 Parents: a1d8e42 Author: Xiaoyu Yao <x...@apache.org> Authored: Mon Aug 17 10:15:56 2015 -0700 Committer: Zhe Zhang <z...@apache.org> Committed: Thu Aug 25 10:10:18 2016 -0700 ---------------------------------------------------------------------- .../hadoop-common/src/site/markdown/Metrics.md | 1 + .../hdfs/server/namenode/FSNamesystem.java | 15 +++++++++++ .../hdfs/server/namenode/FSNamesystemLock.java | 11 ++++++++ .../namenode/metrics/FSNamesystemMBean.java | 9 +++++++ .../hdfs/server/namenode/TestFSNamesystem.java | 28 ++++++++++++++++++++ .../server/namenode/TestNameNodeMXBean.java | 22 ++++++++++++++- 6 files changed, 85 insertions(+), 1 deletion(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-common-project/hadoop-common/src/site/markdown/Metrics.md ---------------------------------------------------------------------- diff --git a/hadoop-common-project/hadoop-common/src/site/markdown/Metrics.md b/hadoop-common-project/hadoop-common/src/site/markdown/Metrics.md index 695641e..a29a7d9 100644 --- a/hadoop-common-project/hadoop-common/src/site/markdown/Metrics.md +++ b/hadoop-common-project/hadoop-common/src/site/markdown/Metrics.md @@ -230,6 +230,7 @@ Each metrics record contains tags such as HAState and Hostname as additional inf | `BlockCapacity` | Current number of block capacity | | `StaleDataNodes` | Current number of DataNodes marked stale due to delayed heartbeat | | `TotalFiles` | Current number of files and directories (same as FilesTotal) | +| `LockQueueLength` | Number of threads waiting to acquire FSNameSystem lock | JournalNode ----------- http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java ---------------------------------------------------------------------- diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java index cd1fe4b..bb99fb2 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java @@ -4936,6 +4936,21 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean, return dir.ezManager.getNumEncryptionZones(); } + /** + * Returns the length of the wait Queue for the FSNameSystemLock. + * + * A larger number here indicates lots of threads are waiting for + * FSNameSystemLock. + * + * @return int - Number of Threads waiting to acquire FSNameSystemLock + */ + @Override + @Metric({"LockQueueLength", "Number of threads waiting to " + + "acquire FSNameSystemLock"}) + public int getFsLockQueueLength() { + return fsLock.getQueueLength(); + } + int getNumberOfDatanodes(DatanodeReportType type) { readLock(); try { http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystemLock.java ---------------------------------------------------------------------- diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystemLock.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystemLock.java index 7e820d8..d239796 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystemLock.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystemLock.java @@ -59,4 +59,15 @@ class FSNamesystemLock implements ReadWriteLock { public boolean isWriteLockedByCurrentThread() { return coarseLock.isWriteLockedByCurrentThread(); } + + /** + * Returns the QueueLength of waiting threads. + * + * A larger number indicates greater lock contention. + * + * @return int - Number of threads waiting on this lock + */ + public int getQueueLength() { + return coarseLock.getQueueLength(); + } } http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/FSNamesystemMBean.java ---------------------------------------------------------------------- diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/FSNamesystemMBean.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/FSNamesystemMBean.java index 580cb78..0fa4841 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/FSNamesystemMBean.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/metrics/FSNamesystemMBean.java @@ -189,4 +189,13 @@ public interface FSNamesystemMBean { * Return the number of encryption zones in the system. */ int getNumEncryptionZones(); + + /** + * Returns the length of the wait Queue for the FSNameSystemLock. + * + * A larger number here indicates lots of threads are waiting for + * FSNameSystemLock. + * @return int - Number of Threads waiting to acquire FSNameSystemLock + */ + int getFsLockQueueLength(); } http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSNamesystem.java ---------------------------------------------------------------------- diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSNamesystem.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSNamesystem.java index 3d0259e..2453542 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSNamesystem.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSNamesystem.java @@ -37,10 +37,15 @@ import org.apache.hadoop.hdfs.server.namenode.ha.HAContext; import org.apache.hadoop.hdfs.server.namenode.ha.HAState; import org.apache.hadoop.hdfs.server.namenode.snapshot.Snapshot; import org.junit.After; +import org.junit.Assert; import org.junit.Test; import org.mockito.Mockito; import org.mockito.internal.util.reflection.Whitebox; +import java.util.concurrent.CountDownLatch; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Executors; + public class TestFSNamesystem { @After @@ -213,4 +218,27 @@ public class TestFSNamesystem { fsn.imageLoadComplete(); assertTrue(fsn.isImageLoaded()); } + + @Test + public void testFSLockGetWaiterCount() throws InterruptedException { + final int threadCount = 3; + final CountDownLatch latch = new CountDownLatch(threadCount); + final FSNamesystemLock rwLock = new FSNamesystemLock(true); + rwLock.writeLock().lock(); + ExecutorService helper = Executors.newFixedThreadPool(threadCount); + + for (int x = 0; x < threadCount; x++) { + helper.execute(new Runnable() { + @Override + public void run() { + latch.countDown(); + rwLock.readLock().lock(); + } + }); + } + + latch.await(); + Assert.assertEquals("Expected number of blocked thread not found", + threadCount, rwLock.getQueueLength()); + } } http://git-wip-us.apache.org/repos/asf/hadoop/blob/e5cb9d9e/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java ---------------------------------------------------------------------- diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java index da7e056..d1e5673 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java @@ -18,6 +18,7 @@ package org.apache.hadoop.hdfs.server.namenode; import com.google.common.util.concurrent.Uninterruptibles; +import org.apache.commons.io.FileUtils; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.FileUtil; @@ -172,7 +173,7 @@ public class TestNameNodeMXBean { // This will cause the first dir to fail. File failedNameDir = new File(nameDirUris.iterator().next()); assertEquals(0, FileUtil.chmod( - new File(failedNameDir, "current").getAbsolutePath(), "000")); + new File(failedNameDir, "current").getAbsolutePath(), "000")); cluster.getNameNodeRpc().rollEditLog(); nameDirStatuses = (String) (mbs.getAttribute(mxbeanName, @@ -372,4 +373,23 @@ public class TestNameNodeMXBean { } } } + + @Test(timeout = 120000) + public void testQueueLength() throws Exception { + final Configuration conf = new Configuration(); + MiniDFSCluster cluster = null; + try { + cluster = new MiniDFSCluster.Builder(conf).numDataNodes(0).build(); + cluster.waitActive(); + MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); + ObjectName mxbeanNameFs = + new ObjectName("Hadoop:service=NameNode,name=FSNamesystem"); + int queueLength = (int) mbs.getAttribute(mxbeanNameFs, "LockQueueLength"); + assertEquals(0, queueLength); + } finally { + if (cluster != null) { + cluster.shutdown(); + } + } + } } --------------------------------------------------------------------- To unsubscribe, e-mail: common-commits-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-commits-h...@hadoop.apache.org
