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Hive QA commented on HIVE-22850: -------------------------------- | (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 5s{color} | {color:blue} Maven dependency ordering for branch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 8m 20s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 37s{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:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 1m 16s{color} | {color:blue} standalone-metastore/metastore-server in master has 181 extant Findbugs warnings. {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 3m 57s{color} | {color:blue} ql in master has 1532 extant Findbugs warnings. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 18s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 0m 28s{color} | {color:blue} Maven dependency ordering for patch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 1m 56s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 31s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 31s{color} | {color:green} the patch passed {color} | | {color:red}-1{color} | {color:red} checkstyle {color} | {color:red} 0m 24s{color} | {color:red} standalone-metastore/metastore-server: The patch generated 6 new + 573 unchanged - 12 fixed = 579 total (was 585) {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} findbugs {color} | {color:green} 5m 48s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 19s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 15s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 32m 54s{color} | {color:black} {color} | \\ \\ || 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-20628/dev-support/hive-personality.sh | | git revision | master / 55207c2 | | Default Java | 1.8.0_111 | | findbugs | v3.0.0 | | checkstyle | http://104.198.109.242/logs//PreCommit-HIVE-Build-20628/yetus/diff-checkstyle-standalone-metastore_metastore-server.txt | | modules | C: standalone-metastore/metastore-server ql U: . | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-20628/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > Optimise lock acquisition in TxnHandler > --------------------------------------- > > Key: HIVE-22850 > URL: https://issues.apache.org/jira/browse/HIVE-22850 > Project: Hive > Issue Type: Improvement > Components: Hive > Reporter: Rajesh Balamohan > Priority: Major > Attachments: HIVE-22850.1.patch, HIVE-22850.2.patch, > HIVE-22850.3.patch, HIVE-22850.4.patch, HIVE-22850.6.patch, Screenshot > 2020-02-07 at 4.14.51 AM.jpg, jumpTableInfo.png > > > With concurrent queries, time taken for lock acquisition increases > substantially. As part of lock acquisition in the query, > {{TxnHandler::checkLock}} gets invoked. This involves getting a mutex and > compare the locks being requested for, with that of existing locks in > {{HIVE_LOCKS}} table. > With concurrent queries, time taken to do this check increase and this > significantly increases the time taken for getting mutex for other threads > (due to select for update). In a synthetic workload, it was in the order of > 10+ seconds. This codepath can be optimized when all lock requests are > SHARED_READ. > > > !Screenshot 2020-02-07 at 4.14.51 AM.jpg|width=743,height=348! -- This message was sent by Atlassian Jira (v8.3.4#803005)