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Hive QA commented on HIVE-21917: -------------------------------- | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || || || || || {color:brown} Prechecks {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:brown} master Compile Tests {color} || | {color:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 2m 26s{color} | {color:blue} Maven dependency ordering for branch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 8m 30s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 45s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 13s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 1m 25s{color} | {color:blue} standalone-metastore/metastore-server in master has 178 extant Findbugs warnings. {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 4m 33s{color} | {color:blue} ql in master has 1539 extant Findbugs warnings. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 28s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 0m 30s{color} | {color:blue} Maven dependency ordering for patch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 2m 15s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 43s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 43s{color} | {color:green} the patch passed {color} | | {color:red}-1{color} | {color:red} checkstyle {color} | {color:red} 0m 29s{color} | {color:red} standalone-metastore/metastore-server: The patch generated 31 new + 627 unchanged - 1 fixed = 658 total (was 628) {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s{color} | {color:green} The patch has no whitespace issues. {color} | | {color:red}-1{color} | {color:red} findbugs {color} | {color:red} 1m 30s{color} | {color:red} standalone-metastore/metastore-server generated 1 new + 178 unchanged - 0 fixed = 179 total (was 178) {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 31s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 16s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 35m 39s{color} | {color:black} {color} | \\ \\ || Reason || Tests || | FindBugs | module:standalone-metastore/metastore-server | | | org.apache.hadoop.hive.metastore.txn.CompactionTxnHandler.findPotentialCompactions(int, long) passes a nonconstant String to an execute or addBatch method on an SQL statement At CompactionTxnHandler.java:String to an execute or addBatch method on an SQL statement At CompactionTxnHandler.java:[line 94] | \\ \\ || Subsystem || Report/Notes || | Optional Tests | asflicense javac javadoc findbugs checkstyle compile | | uname | Linux hiveptest-server-upstream 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u5 (2017-09-19) x86_64 GNU/Linux | | Build tool | maven | | Personality | /data/hiveptest/working/yetus_PreCommit-HIVE-Build-19587/dev-support/hive-personality.sh | | git revision | master / a70408a | | Default Java | 1.8.0_111 | | findbugs | v3.0.0 | | checkstyle | http://104.198.109.242/logs//PreCommit-HIVE-Build-19587/yetus/diff-checkstyle-standalone-metastore_metastore-server.txt | | findbugs | http://104.198.109.242/logs//PreCommit-HIVE-Build-19587/yetus/new-findbugs-standalone-metastore_metastore-server.html | | modules | C: standalone-metastore/metastore-server ql U: . | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-19587/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > COMPLETED_TXN_COMPONENTS table is never cleaned up unless Compactor runs > ------------------------------------------------------------------------ > > Key: HIVE-21917 > URL: https://issues.apache.org/jira/browse/HIVE-21917 > Project: Hive > Issue Type: Bug > Components: Transactions > Affects Versions: 3.1.0, 3.1.1 > Reporter: Craig Condit > Assignee: Denys Kuzmenko > Priority: Major > Attachments: HIVE-21917.1.patch, HIVE-21917.2.patch, > HIVE-21917.3.patch, HIVE-21917.4.patch, HIVE-21917.5.patch, HIVE-21917.6.patch > > > The Initiator thread in the metastore repeatedly loops over entries in the > COMPLETED_TXN_COMPONENTS table to determine which partitions / tables might > need to be compacted. However, entries are never removed from this table > except by a completed Compactor run. > In a cluster where most tables / partitions are write-once read-many, this > results in stale entries in this table never being cleaned up. In a small > test cluster, we have observed approximately 45k entries in this table > (virtually equal to the number of partitions in the cluster) while < 100 of > these tables have delta files at all. Since most of the tables will never get > enough writes to trigger a compaction (and in fact have only ever been > written to once), the initiator thread keeps trying to evaluate them on every > loop. > On this test cluster, it takes approximately 10 minutes to loop through all > the entries and results in severe performance degradation on metastore > operations. With the default run timing of 5 minutes, the initiator basically > never stops running. > On a production cluster with 2M partitions, this would be a non-starter. > The initiator thread should proactively remove entries from > COMPLETED_TXN_COMPONENTS when it determines that a compaction is not needed, > so that they are not evaluated again on the next loop. > -- This message was sent by Atlassian Jira (v8.3.4#803005)