From f6550361f77ab08e773fd93cda60b35047d048d3 Mon Sep 17 00:00:00 2001 From: Arpit Agarwal Date: Sun, 28 Jun 2015 14:51:17 -0700 Subject: [PATCH] HDFS-8681. BlockScanner is incorrectly disabled by default. (Contributed by Arpit Agarwal) --- hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt | 3 ++ .../org/apache/hadoop/hdfs/DFSConfigKeys.java | 2 +- .../hdfs/server/datanode/BlockScanner.java | 36 +++++++++++++++---- .../src/main/resources/hdfs-default.xml | 9 +++-- .../fsdataset/impl/TestFsDatasetImpl.java | 1 + 5 files changed, 41 insertions(+), 10 deletions(-) diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt index 9dfa3d7536d..2f178e67dd3 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt +++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt @@ -149,6 +149,9 @@ Release 2.7.1 - UNRELEASED HDFS-8626. Reserved RBW space is not released if creation of RBW File fails. (kanaka kumar avvaru via Arpit Agarwal) + HDFS-8681. BlockScanner is incorrectly disabled by default. + (Arpit Agarwal) + Release 2.7.0 - 2015-04-20 INCOMPATIBLE CHANGES diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java index b8d203e3cd5..a8d7159b991 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java @@ -453,7 +453,7 @@ public class DFSConfigKeys extends CommonConfigurationKeys { public static final String DFS_DATANODE_MAX_RECEIVER_THREADS_KEY = "dfs.datanode.max.transfer.threads"; public static final int DFS_DATANODE_MAX_RECEIVER_THREADS_DEFAULT = 4096; public static final String DFS_DATANODE_SCAN_PERIOD_HOURS_KEY = "dfs.datanode.scan.period.hours"; - public static final int DFS_DATANODE_SCAN_PERIOD_HOURS_DEFAULT = 0; + public static final int DFS_DATANODE_SCAN_PERIOD_HOURS_DEFAULT = 21 * 24; // 3 weeks. public static final String DFS_BLOCK_SCANNER_VOLUME_BYTES_PER_SECOND = "dfs.block.scanner.volume.bytes.per.second"; public static final long DFS_BLOCK_SCANNER_VOLUME_BYTES_PER_SECOND_DEFAULT = 1048576L; public static final String DFS_DATANODE_TRANSFERTO_ALLOWED_KEY = "dfs.datanode.transferTo.allowed"; diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockScanner.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockScanner.java index b0248c50d9c..9c4dd10f005 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockScanner.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockScanner.java @@ -115,6 +115,34 @@ public class BlockScanner { } } + /** + * Determine the configured block scanner interval. + * + * For compatibility with prior releases of HDFS, if the + * configured value is zero then the scan period is + * set to 3 weeks. + * + * If the configured value is less than zero then the scanner + * is disabled. + * + * @param conf Configuration object. + * @return block scan period in milliseconds. + */ + private static long getConfiguredScanPeriodMs(Configuration conf) { + long tempScanPeriodMs = getUnitTestLong( + conf, INTERNAL_DFS_DATANODE_SCAN_PERIOD_MS, + TimeUnit.MILLISECONDS.convert(conf.getLong( + DFS_DATANODE_SCAN_PERIOD_HOURS_KEY, + DFS_DATANODE_SCAN_PERIOD_HOURS_DEFAULT), TimeUnit.HOURS)); + + if (tempScanPeriodMs == 0) { + tempScanPeriodMs = TimeUnit.MILLISECONDS.convert( + DFS_DATANODE_SCAN_PERIOD_HOURS_DEFAULT, TimeUnit.HOURS); + } + + return tempScanPeriodMs; + } + @SuppressWarnings("unchecked") Conf(Configuration conf) { this.targetBytesPerSec = Math.max(0L, conf.getLong( @@ -123,11 +151,7 @@ public class BlockScanner { this.maxStalenessMs = Math.max(0L, getUnitTestLong(conf, INTERNAL_DFS_BLOCK_SCANNER_MAX_STALENESS_MS, INTERNAL_DFS_BLOCK_SCANNER_MAX_STALENESS_MS_DEFAULT)); - this.scanPeriodMs = Math.max(0L, - getUnitTestLong(conf, INTERNAL_DFS_DATANODE_SCAN_PERIOD_MS, - TimeUnit.MILLISECONDS.convert(conf.getLong( - DFS_DATANODE_SCAN_PERIOD_HOURS_KEY, - DFS_DATANODE_SCAN_PERIOD_HOURS_DEFAULT), TimeUnit.HOURS))); + this.scanPeriodMs = getConfiguredScanPeriodMs(conf); this.cursorSaveMs = Math.max(0L, getUnitTestLong(conf, INTERNAL_DFS_BLOCK_SCANNER_CURSOR_SAVE_INTERVAL_MS, INTERNAL_DFS_BLOCK_SCANNER_CURSOR_SAVE_INTERVAL_MS_DEFAULT)); @@ -159,7 +183,7 @@ public class BlockScanner { * no threads will start. */ public boolean isEnabled() { - return (conf.scanPeriodMs) > 0 && (conf.targetBytesPerSec > 0); + return (conf.scanPeriodMs > 0) && (conf.targetBytesPerSec > 0); } /** diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml index f50bdc19efb..41997981c3e 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml @@ -1024,11 +1024,14 @@ dfs.datanode.scan.period.hours - 0 + 504 - If this is 0 or negative, the DataNode's block scanner will be - disabled. If this is positive, the DataNode will not scan any + If this is positive, the DataNode will not scan any individual block more than once in the specified scan period. + If this is negative, the block scanner is disabled. + If this is set to zero, then the default value of 504 hours + or 3 weeks is used. Prior versions of HDFS incorrectly documented + that setting this key to zero will disable the block scanner. diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsDatasetImpl.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsDatasetImpl.java index 03e5dc5505d..5946080a4fb 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsDatasetImpl.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsDatasetImpl.java @@ -264,6 +264,7 @@ public class TestFsDatasetImpl { public void testChangeVolumeWithRunningCheckDirs() throws IOException { RoundRobinVolumeChoosingPolicy blockChooser = new RoundRobinVolumeChoosingPolicy<>(); + conf.setLong(DFSConfigKeys.DFS_DATANODE_SCAN_PERIOD_HOURS_KEY, -1); final BlockScanner blockScanner = new BlockScanner(datanode, conf); final FsVolumeList volumeList = new FsVolumeList( Collections.emptyList(), blockScanner, blockChooser);