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Hadoop QA commented on HBASE-21387: ----------------------------------- | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:blue}0{color} | {color:blue} reexec {color} | {color:blue} 0m 13s{color} | {color:blue} Docker mode activated. {color} | | {color:blue}0{color} | {color:blue} patch {color} | {color:blue} 0m 3s{color} | {color:blue} The patch file was not named according to hbase's naming conventions. Please see https://yetus.apache.org/documentation/0.8.0/precommit-patchnames for instructions. {color} | || || || || {color:brown} Prechecks {color} || | {color:green}+1{color} | {color:green} hbaseanti {color} | {color:green} 0m 0s{color} | {color:green} Patch does not have any anti-patterns. {color} | | {color:green}+1{color} | {color:green} @author {color} | {color:green} 0m 0s{color} | {color:green} The patch does not contain any @author tags. {color} | | {color:orange}-0{color} | {color:orange} test4tests {color} | {color:orange} 0m 0s{color} | {color:orange} The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch. {color} | || || || || {color:brown} master Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 4m 3s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 48s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 5s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} shadedjars {color} | {color:green} 3m 44s{color} | {color:green} branch has no errors when building our shaded downstream artifacts. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 1m 56s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 30s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 4m 5s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 47s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 47s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 5s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s{color} | {color:green} The patch has no whitespace issues. {color} | | {color:green}+1{color} | {color:green} shadedjars {color} | {color:green} 3m 49s{color} | {color:green} patch has no errors when building our shaded downstream artifacts. {color} | | {color:green}+1{color} | {color:green} hadoopcheck {color} | {color:green} 8m 19s{color} | {color:green} Patch does not cause any errors with Hadoop 2.7.4 or 3.0.0. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 2m 6s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 30s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:red}-1{color} | {color:red} unit {color} | {color:red}134m 7s{color} | {color:red} hbase-server in the patch failed. {color} | | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 28s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black}170m 8s{color} | {color:black} {color} | \\ \\ || Reason || Tests || | Failed junit tests | hadoop.hbase.client.TestMobRestoreSnapshotFromClientAfterSplittingRegions | \\ \\ || Subsystem || Report/Notes || | Docker | Client=17.05.0-ce Server=17.05.0-ce Image:yetus/hbase:b002b0b | | JIRA Issue | HBASE-21387 | | JIRA Patch URL | https://issues.apache.org/jira/secure/attachment/12949323/21387.addendum.txt | | Optional Tests | dupname asflicense javac javadoc unit findbugs shadedjars hadoopcheck hbaseanti checkstyle compile | | uname | Linux cb172c1a4402 4.4.0-138-generic #164-Ubuntu SMP Tue Oct 2 17:16:02 UTC 2018 x86_64 GNU/Linux | | Build tool | maven | | Personality | /home/jenkins/jenkins-slave/workspace/PreCommit-HBASE-Build/component/dev-support/hbase-personality.sh | | git revision | master / 6d0dc960e6 | | maven | version: Apache Maven 3.5.4 (1edded0938998edf8bf061f1ceb3cfdeccf443fe; 2018-06-17T18:33:14Z) | | Default Java | 1.8.0_181 | | findbugs | v3.1.0-RC3 | | unit | https://builds.apache.org/job/PreCommit-HBASE-Build/15102/artifact/patchprocess/patch-unit-hbase-server.txt | | Test Results | https://builds.apache.org/job/PreCommit-HBASE-Build/15102/testReport/ | | Max. process+thread count | 4863 (vs. ulimit of 10000) | | modules | C: hbase-server U: hbase-server | | Console output | https://builds.apache.org/job/PreCommit-HBASE-Build/15102/console | | Powered by | Apache Yetus 0.8.0 http://yetus.apache.org | This message was automatically generated. > Race condition surrounding in progress snapshot handling in snapshot cache > leads to loss of snapshot files > ---------------------------------------------------------------------------------------------------------- > > Key: HBASE-21387 > URL: https://issues.apache.org/jira/browse/HBASE-21387 > Project: HBase > Issue Type: Bug > Reporter: Ted Yu > Assignee: Ted Yu > Priority: Major > Labels: snapshot > Fix For: 3.0.0, 1.5.0, 1.3.3, 2.2.0, 2.0.3, 1.4.9, 2.1.2, 1.2.10 > > Attachments: 0001-UT.patch, 21387-suggest.txt, 21387.addendum.txt, > 21387.dbg.txt, 21387.v10.txt, 21387.v11.txt, 21387.v12.txt, 21387.v2.txt, > 21387.v3.txt, 21387.v6.txt, 21387.v7.txt, 21387.v8.txt, 21387.v9.txt, > HBASE-21387.branch-1.2.patch, HBASE-21387.branch-1.3.patch, > HBASE-21387.branch-1.patch, HBASE-21387.v13.patch, HBASE-21387.v14.patch, > HBASE-21387.v15.patch, HBASE-21387.v16.patch, HBASE-21387.v17.patch, > two-pass-cleaner.v4.txt, two-pass-cleaner.v6.txt, two-pass-cleaner.v9.txt > > > During recent report from customer where ExportSnapshot failed: > {code} > 2018-10-09 18:54:32,559 ERROR [VerifySnapshot-pool1-t2] > snapshot.SnapshotReferenceUtil: Can't find hfile: > 44f6c3c646e84de6a63fe30da4fcb3aa in the real > (hdfs://in.com:8020/apps/hbase/data/data/.../a/44f6c3c646e84de6a63fe30da4fcb3aa) > or archive > (hdfs://in.com:8020/apps/hbase/data/archive/data/.../a/44f6c3c646e84de6a63fe30da4fcb3aa) > directory for the primary table. > {code} > We found the following in log: > {code} > 2018-10-09 18:54:23,675 DEBUG > [00:16000.activeMasterManager-HFileCleaner.large-1539035367427] > cleaner.HFileCleaner: Removing: > hdfs:///apps/hbase/data/archive/data/.../a/44f6c3c646e84de6a63fe30da4fcb3aa > from archive > {code} > The root cause is race condition surrounding in progress snapshot(s) handling > between refreshCache() and getUnreferencedFiles(). > There are two callers of refreshCache: one from RefreshCacheTask#run and the > other from SnapshotHFileCleaner. > Let's look at the code of refreshCache: > {code} > if (!name.equals(SnapshotDescriptionUtils.SNAPSHOT_TMP_DIR_NAME)) { > {code} > whose intention is to exclude in progress snapshot(s). > Suppose when the RefreshCacheTask runs refreshCache, there is some in > progress snapshot (about to finish). > When SnapshotHFileCleaner calls getUnreferencedFiles(), it sees that > lastModifiedTime is up to date. So cleaner proceeds to check in progress > snapshot(s). However, the snapshot has completed by that time, resulting in > some file(s) deemed unreferenced. > Here is timeline given by Josh illustrating the scenario: > At time T0, we are checking if F1 is referenced. At time T1, there is a > snapshot S1 in progress that is referencing a file F1. refreshCache() is > called, but no completed snapshot references F1. At T2, the snapshot S1, > which references F1, completes. At T3, we check in-progress snapshots and S1 > is not included. Thus, F1 is marked as unreferenced even though S1 references > it. -- This message was sent by Atlassian JIRA (v7.6.3#76005)