[ https://issues.apache.org/jira/browse/HIVE-10494?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15900798#comment-15900798 ]
Zhaofei Meng edited comment on HIVE-10494 at 3/8/17 6:40 AM: ------------------------------------------------------------- Try to adjust jvm parameter and set CMSInitiatingOccupancyFraction 60. was (Author: 5feixiang): Try to adjust jvm parameter and set CMSInitiatingOccupancyFraction smaller. > hive metastore server can't release its java heap with no work on it > -------------------------------------------------------------------- > > Key: HIVE-10494 > URL: https://issues.apache.org/jira/browse/HIVE-10494 > Project: Hive > Issue Type: Bug > Components: Metastore > Affects Versions: 0.13.0 > Environment: cloudera cdh 5.2.0 > 10 nodes > 128G ram, 10T disk, 32core CPU for each node > using impala for data analysis > Reporter: liqida > > I use impala for data analysis > after a long time runing , impala DDL statements need a long time to complete > "Planning finished" and "DML Metastore update finished" steps. > Both of them take 50 seconds and more. > I found that HMS java heap has affected it so much .and I restart the hive > metastore server , the problem fixed . > The HMS java ops like this : > -XX:+UseParNewGC > -XX:+UseConcMarkSweepGC > -XX:-CMSConcurrentMTEnabled > -XX:CMSInitiatingOccupancyFraction=70 > -XX:+CMSParallelRemarkEnabled > -XX:+UseCMSCompactAtFullCollection > -XX:CMSFullGCsBeforeCompaction=0 > -XX:SurvivorRatio=1 > and the total heap size is 3GB > after 3 days or less , I found the old genaration is full , and no matter > what kind of GC I tried , it never works . > And then , after the whole work is done() , I run " jmap -F -histo PID " > I found this : > Object Histogram: > num #instances #bytes Class description > -------------------------------------------------------------------------- > 1: 3955457 696160432 com.mysql.jdbc.JDBC4ResultSet > 2: 3942714 630834240 com.mysql.jdbc.StatementImpl > 3: 4051520 194472960 java.util.HashMap > 4: 4714330 150858560 java.util.HashMap$Entry > 5: 3990264 63844224 java.util.HashSet > 6: 3978657 63658512 java.util.HashMap$KeySet > 7: 3955458 63463696 com.mysql.jdbc.Field[] > 8: 3964025 63424400 > java.util.concurrent.atomic.AtomicBoolean > 9: 3961293 63380688 java.lang.Object > I think this is the causation > So, what can I do with this , should I change some configuration or do > something to fix this , or HMS has any CACHE ? THANKS > BTW: Hive version 0.13.0 , I only use impala -- This message was sent by Atlassian JIRA (v6.3.15#6346)