[ https://issues.apache.org/jira/browse/HBASE-13082?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15113298#comment-15113298 ]
Hudson commented on HBASE-13082: -------------------------------- SUCCESS: Integrated in HBase-1.3-IT #454 (See [https://builds.apache.org/job/HBase-1.3-IT/454/]) Revert "HBASE-14970 Backport HBASE-13082 and its sub-jira to branch-1 (stack: rev a5228a0b4d8b4c6b9bab58e1eee015393edaaade) * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java * hbase-server/src/main/java/org/apache/hadoop/hbase/executor/ExecutorService.java * hbase-server/src/test/java/org/apache/hadoop/hbase/backup/example/TestZooKeeperTableArchiveClient.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedStoreScanner.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionMergeTransactionOnCluster.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/MockStoreFile.java * hbase-client/src/main/java/org/apache/hadoop/hbase/executor/ExecutorType.java * hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestSnapshotFromMaster.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/CompactedHFilesDischargeHandler.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCompactedHFilesDischarger.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestEncryptionKeyRotation.java * hbase-client/src/main/java/org/apache/hadoop/hbase/executor/EventType.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionReplayEvents.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreScanner.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/CompactedHFilesDischarger.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileManager.java * hbase-server/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStore.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFile.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/OnlineRegions.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/DefaultStoreFileManager.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ChangedReadersObserver.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java * hbase-server/src/test/java/org/apache/hadoop/hbase/MockRegionServerServices.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HStore.java * hbase-server/src/test/java/org/apache/hadoop/hbase/io/TestHeapSize.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestWideScanner.java * hbase-server/src/test/java/org/apache/hadoop/hbase/TestIOFencing.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStripeStoreFileManager.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileScanner.java * hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/Store.java * hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestRegionReplicas.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreScanner.java * hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/compactions/CompactionConfiguration.java > Coarsen StoreScanner locks to RegionScanner > ------------------------------------------- > > Key: HBASE-13082 > URL: https://issues.apache.org/jira/browse/HBASE-13082 > Project: HBase > Issue Type: Bug > Components: Performance, Scanners > Reporter: Lars Hofhansl > Assignee: ramkrishna.s.vasudevan > Fix For: 2.0.0 > > Attachments: 13082-test.txt, 13082-v2.txt, 13082-v3.txt, > 13082-v4.txt, 13082.txt, 13082.txt, HBASE-13082.pdf, HBASE-13082_1.pdf, > HBASE-13082_12.patch, HBASE-13082_13.patch, HBASE-13082_14.patch, > HBASE-13082_15.patch, HBASE-13082_16.patch, HBASE-13082_17.patch, > HBASE-13082_18.patch, HBASE-13082_19.patch, HBASE-13082_1_WIP.patch, > HBASE-13082_2.pdf, HBASE-13082_2_WIP.patch, HBASE-13082_3.patch, > HBASE-13082_4.patch, HBASE-13082_9.patch, HBASE-13082_9.patch, > HBASE-13082_withoutpatch.jpg, HBASE-13082_withpatch.jpg, > LockVsSynchronized.java, gc.png, gc.png, gc.png, hits.png, next.png, next.png > > > Continuing where HBASE-10015 left of. > We can avoid locking (and memory fencing) inside StoreScanner by deferring to > the lock already held by the RegionScanner. > In tests this shows quite a scan improvement and reduced CPU (the fences make > the cores wait for memory fetches). > There are some drawbacks too: > * All calls to RegionScanner need to be remain synchronized > * Implementors of coprocessors need to be diligent in following the locking > contract. For example Phoenix does not lock RegionScanner.nextRaw() and > required in the documentation (not picking on Phoenix, this one is my fault > as I told them it's OK) > * possible starving of flushes and compaction with heavy read load. > RegionScanner operations would keep getting the locks and the > flushes/compactions would not be able finalize the set of files. > I'll have a patch soon. -- This message was sent by Atlassian JIRA (v6.3.4#6332)