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Hadoop QA commented on HBASE-15968: ----------------------------------- | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:blue}0{color} | {color:blue} reexec {color} | {color:blue} 0m 17s{color} | {color:blue} Docker mode activated. {color} | | {color:blue}0{color} | {color:blue} rubocop {color} | {color:blue} 0m 0s{color} | {color:blue} rubocop was not available. {color} | | {color:blue}0{color} | {color:blue} ruby-lint {color} | {color:blue} 0m 0s{color} | {color:blue} Ruby-lint was not available. {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:green}+1{color} | {color:green} test4tests {color} | {color:green} 0m 0s{color} | {color:green} The patch appears to include 15 new or modified test files. {color} | | {color:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 0m 31s{color} | {color:blue} Maven dependency ordering for branch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 3m 36s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 24s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 22s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} mvneclipse {color} | {color:green} 0m 43s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 4m 6s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 58s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 0m 18s{color} | {color:blue} Maven dependency ordering for patch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 1m 27s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 14s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 14s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 20s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} mvneclipse {color} | {color:green} 0m 45s{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} hadoopcheck {color} | {color:green} 31m 20s{color} | {color:green} Patch does not cause any errors with Hadoop 2.6.1 2.6.2 2.6.3 2.6.4 2.6.5 2.7.1 2.7.2 2.7.3 or 3.0.0-alpha4. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 3m 48s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 53s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} unit {color} | {color:green} 2m 39s{color} | {color:green} hbase-client in the patch passed. {color} | | {color:red}-1{color} | {color:red} unit {color} | {color:red} 23m 38s{color} | {color:red} hbase-server in the patch failed. {color} | | {color:red}-1{color} | {color:red} unit {color} | {color:red} 1m 28s{color} | {color:red} hbase-shell in the patch failed. {color} | | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 26s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 82m 53s{color} | {color:black} {color} | \\ \\ || Reason || Tests || | Failed junit tests | hadoop.hbase.io.hfile.TestBlockCacheReporting | | | hadoop.hbase.client.TestShell | \\ \\ || Subsystem || Report/Notes || | Docker | Client=1.12.3 Server=1.12.3 Image:yetus/hbase:757bf37 | | JIRA Issue | HBASE-15968 | | JIRA Patch URL | https://issues.apache.org/jira/secure/attachment/12878140/HBASE-15968.v06.patch | | Optional Tests | asflicense javac javadoc unit findbugs hadoopcheck hbaseanti checkstyle compile rubocop ruby_lint | | uname | Linux 832de49dbdf4 3.13.0-119-generic #166-Ubuntu SMP Wed May 3 12:18:55 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux | | Build tool | maven | | Personality | /home/jenkins/jenkins-slave/workspace/PreCommit-HBASE-Build@2/component/dev-support/hbase-personality.sh | | git revision | master / 01db60d | | Default Java | 1.8.0_131 | | findbugs | v3.1.0-RC3 | | unit | https://builds.apache.org/job/PreCommit-HBASE-Build/7732/artifact/patchprocess/patch-unit-hbase-server.txt | | unit | https://builds.apache.org/job/PreCommit-HBASE-Build/7732/artifact/patchprocess/patch-unit-hbase-shell.txt | | Test Results | https://builds.apache.org/job/PreCommit-HBASE-Build/7732/testReport/ | | modules | C: hbase-client hbase-server hbase-shell U: . | | Console output | https://builds.apache.org/job/PreCommit-HBASE-Build/7732/console | | Powered by | Apache Yetus 0.4.0 http://yetus.apache.org | This message was automatically generated. > New behavior of versions considering mvcc and ts rather than ts only > -------------------------------------------------------------------- > > Key: HBASE-15968 > URL: https://issues.apache.org/jira/browse/HBASE-15968 > Project: HBase > Issue Type: New Feature > Reporter: Phil Yang > Assignee: Phil Yang > Fix For: 3.0.0 > > Attachments: HBASE-15968.v05.patch, HBASE-15968.v06.patch, > HBASE-15968-v1.patch, HBASE-15968-v2.patch, HBASE-15968-v3.patch, > HBASE-15968-v4.patch > > > In HBase book, we have a section in Versions called "Current Limitations" see > http://hbase.apache.org/book.html#_current_limitations > {quote} > 28.3. Current Limitations > 28.3.1. Deletes mask Puts > Deletes mask puts, even puts that happened after the delete was entered. See > HBASE-2256. Remember that a delete writes a tombstone, which only disappears > after then next major compaction has run. Suppose you do a delete of > everything ⇐ T. After this you do a new put with a timestamp ⇐ T. This put, > even if it happened after the delete, will be masked by the delete tombstone. > Performing the put will not fail, but when you do a get you will notice the > put did have no effect. It will start working again after the major > compaction has run. These issues should not be a problem if you use > always-increasing versions for new puts to a row. But they can occur even if > you do not care about time: just do delete and put immediately after each > other, and there is some chance they happen within the same millisecond. > 28.3.2. Major compactions change query results > …create three cell versions at t1, t2 and t3, with a maximum-versions > setting of 2. So when getting all versions, only the values at t2 and t3 will > be returned. But if you delete the version at t2 or t3, the one at t1 will > appear again. Obviously, once a major compaction has run, such behavior will > not be the case anymore… (See Garbage Collection in Bending time in HBase.) > {quote} > These limitations result from the current implementation on multi-versions: > we only consider timestamp, no matter when it comes; we will not remove old > version immediately if there are enough number of new versions. > So we can get a stronger semantics of versions by two guarantees: > 1, Delete will not mask Put that comes after it. > 2, If a version is masked by enough number of higher versions (VERSIONS in > cf's conf), it will never be seen any more. > Some examples for understanding: > (delete t<=3 means use Delete.addColumns to delete all versions whose ts is > not greater than 3, and delete t3 means use Delete.addColumn to delete the > version whose ts=3) > case 1: put t2 -> put t3 -> delete t<=3 -> put t1, and we will get t1 because > the put is after delete. > case 2: maxversion=2, put t1 -> put t2 -> put t3 -> delete t3, and we will > always get t2 no matter if there is a major compaction, because t1 is masked > when we put t3 so t1 will never be seen. > case 3: maxversion=2, put t1 -> put t2 -> put t3 -> delete t2 -> delete t3, > and we will get nothing. > case 4: maxversion=3, put t1 -> put t2 -> put t3 -> delete t2 -> delete t3, > and we will get t1 because it is not masked. > case 5: maxversion=2, put t1 -> put t2 -> put t3 -> delete t3 -> put t1, and > we can get t3+t1 because when we put t1 at second time it is the 2nd latest > version and it can be read. > case 6:maxversion=2, put t3->put t2->put t1, and we will get t3+t2 just like > what we can get now, ts is still the key of versions. > Different VERSIONS may result in different results even the size of result is > smaller than VERSIONS(see case 3 and 4). So Get/Scan.setMaxVersions will be > handled at end after we read correct data according to CF's VERSIONS setting. > The semantics is different from the current HBase, and we may need more logic > to support the new semantic, so it is configurable and default is disabled. -- This message was sent by Atlassian JIRA (v6.4.14#64029)