[ https://issues.apache.org/jira/browse/HIVE-21686?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16839180#comment-16839180 ]
Hive QA commented on HIVE-21686: -------------------------------- | (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 16s{color} | {color:blue} Maven dependency ordering for branch {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 7m 37s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 0m 42s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 31s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 0m 33s{color} | {color:blue} common in master has 62 extant Findbugs warnings. {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 0m 44s{color} | {color:blue} llap-server in master has 81 extant Findbugs warnings. {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:blue}0{color} | {color:blue} mvndep {color} | {color:blue} 0m 31s{color} | {color:blue} Maven dependency ordering for patch {color} | | {color:red}-1{color} | {color:red} mvninstall {color} | {color:red} 0m 23s{color} | {color:red} llap-server in the patch failed. {color} | | {color:red}-1{color} | {color:red} compile {color} | {color:red} 0m 23s{color} | {color:red} llap-server in the patch failed. {color} | | {color:red}-1{color} | {color:red} javac {color} | {color:red} 0m 23s{color} | {color:red} llap-server in the patch failed. {color} | | {color:red}-1{color} | {color:red} checkstyle {color} | {color:red} 0m 15s{color} | {color:red} llap-server: The patch generated 12 new + 85 unchanged - 15 fixed = 97 total (was 100) {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} 0m 23s{color} | {color:red} llap-server in the patch failed. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 32s{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} 17m 57s{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-17204/dev-support/hive-personality.sh | | git revision | master / af97e84 | | Default Java | 1.8.0_111 | | findbugs | v3.0.0 | | mvninstall | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus/patch-mvninstall-llap-server.txt | | compile | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus/patch-compile-llap-server.txt | | javac | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus/patch-compile-llap-server.txt | | checkstyle | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus/diff-checkstyle-llap-server.txt | | findbugs | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus/patch-findbugs-llap-server.txt | | modules | C: common llap-server U: . | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-17204/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > Brute Force eviction can lead to a random uncontrolled eviction pattern. > ------------------------------------------------------------------------ > > Key: HIVE-21686 > URL: https://issues.apache.org/jira/browse/HIVE-21686 > Project: Hive > Issue Type: Bug > Reporter: slim bouguerra > Assignee: slim bouguerra > Priority: Major > Labels: pull-request-available > Attachments: Cache_hitrate_improvement.csv, HIVE-21686.2.patch, > HIVE-21686.3.patch, HIVE-21686.4.patch, HIVE-21686.patch > > Time Spent: 3.5h > Remaining Estimate: 0h > > Current logic used by brute force eviction can lead to a perpetual random > eviction pattern. > For instance if the cache build a small pocket of free memory where the total > size is greater than incoming allocation request, the allocator will randomly > evict block that fits a particular size. > This can happen over and over therefore all the eviction will be random. > In Addition this random eviction will lead a leak in the linked list > maintained by the policy since it does not know anymore about what is evicted > and what not. > The improvement of this patch is very substantial to TPC-DS benchmark. I > have tested it with 10TB scale 9 llap nodes and 32GB cache size per node. > The patch has showed very noticeable difference in the Hit rate for raw > number [^Cache_hitrate_improvement.csv] -- This message was sent by Atlassian JIRA (v7.6.3#76005)