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javahadoopgarbage-collectionmetricsambari

Automatic deletion of rotated gc.log files

we have hadoop cluster version 2.6.4 while metrics collector installed on one of our Linux servers 

root@master02 ambari-metrics-collector]#  rpm -qa | grep metrics-collector
ambari-metrics-collector-2.6.1.0-143.x86_64

under /var/log/ambari-metrics-collector , we have file of gc.log from Jul last year , and we want to automatic deletion of rotated gc.log files

[root@master02 ambari-metrics-collector]# ls -ltr | grep gc.log | grep -v collector| more
-rw-r--r--. 1 ams  hadoop      1430 Jul 13  2017 gc.log-201707131628
-rw-r--r--  1 ams  hadoop 178518767 Aug 28  2017 gc.log-201707160637
-rw-r--r--  1 ams  hadoop 128748829 Sep 17  2017 gc.log-201708280731
-rw-r--r--  1 ams  hadoop     60849 Sep 18  2017 gc.log-201709181421
-rw-r--r--  1 ams  hadoop     82562 Sep 18  2017 gc.log-201709181424
-rw-r--r--  1 ams  hadoop 164381669 Oct 19  2017 gc.log-201709181508
-rw-r--r--  1 ams  hadoop     46149 Oct 19  2017 gc.log-201710191738
-rw-r--r--  1 ams  hadoop  13763796 Oct 23  2017 gc.log-201710200633
-rw-r--r--  1 ams  hadoop   1048289 Oct 23  2017 gc.log-201710231021
-rw-r--r--  1 ams  hadoop   3473874 Oct 24  2017 gc.log-201710231649
-rw-r--r--  1 ams  hadoop 137289030 Nov 15  2017 gc.log-201710241352
-rw-r--r--  1 ams  hadoop   8037548 Nov 16  2017 gc.log-201711151355
-rw-r--r--  1 ams  hadoop  23919164 Nov 19  2017 gc.log-201711161246
-rw-r--r--  1 ams  hadoop 139759594 Dec  6 16:35 gc.log-201711191241
-rw-r--r--  1 ams  hadoop 184118442 Dec 25 16:13 gc.log-201712061635
-rw-r--r--  1 ams  hadoop      1440 Jan  1 04:38 gc.log-201712251613
-rw-r--r--  1 ams  hadoop      1437 Jan 10 00:03 gc.log-201801021532
-rw-r--r--  1 ams  hadoop      1439 Jan 10 01:04 gc.log-201801100004
-rw-r--r--  1 ams  hadoop      3637 Jan 10 01:11 gc.log-201801100105
-rw-r--r--  1 ams  hadoop      1437 Jan 10 01:16 gc.log-201801100113
-rw-r--r--  1 ams  hadoop      3636 Jan 10 01:24 gc.log-201801100118
-rw-r--r--  1 ams  hadoop      1438 Jan 10 01:35 gc.log-201801100126
-rw-r--r--  1 ams  hadoop      1438 Jan 10 01:42 gc.log-201801100137
-rw-r--r--  1 ams  hadoop      1436 Jan 10 02:14 gc.log-201801100144
-rw-r--r--  1 ams  hadoop      8353 Jan 10 02:19 gc.log-201801100216
-rw-r--r--  1 ams  hadoop      1437 Jan 11 09:08 gc.log-201801110730
-rw-r--r--  1 ams  hadoop      1436 Jan 11 09:19 gc.log-201801110909
-rw-r--r--  1 ams  hadoop       766 Jan 11 09:20 gc.log-201801110920
-rw-r--r--  1 ams  hadoop       765 Jan 11 09:26 gc.log-201801110926

from Advanced ams-hbase-env in ambari gui we see the following :

{% if java_version < 8 %}
export HBASE_MASTER_OPTS=" -XX:PermSize=64m -XX:MaxPermSize={{hbase_master_maxperm_size}} -Xms{{hbase_heapsize}} -Xmx{{hbase_heapsize}} -Xmn{{hbase_master_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly"
export HBASE_REGIONSERVER_OPTS="-XX:MaxPermSize=128m -Xmn{{regionserver_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -Xms{{regionserver_heapsize}} -Xmx{{regionserver_heapsize}}"
{% else %}
export HBASE_MASTER_OPTS=" -Xms{{hbase_heapsize}} -Xmx{{hbase_heapsize}} -Xmn{{hbase_master_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly"
export HBASE_REGIONSERVER_OPTS=" -Xmn{{regionserver_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -Xms{{regionserver_heapsize}} -Xmx{{regionserver_heapsize}}"
{% endif %}

and we try to set in HBASE_MASTER_OPTS or HBASE_REGIONSERVER_OPTS
the -XX:NumberOfGClogFiles=10 in order to get only 10 gc.log files , but metrics collector failed to start , seems because incorrect syntax

refernce - http://www.oracle.com/technetwork/java/vmoptions-jsp-140102.html

export HBASE_MASTER_OPTS=" -XX:PermSize=64m -XX:MaxPermSize={{hbase_master_maxperm_size}} -Xms{{hbase_heapsize}} -Xmx{{hbase_heapsize}} -Xmn{{hbase_master_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -XX:NumberOfGClogFiles=1"

please advice how to perform automatic deletion of rotated gc.log files

Solution

  • When we want to do GC log rotation then in that case we will have to define few properties together to make it work appropriately like following along with the "-Xloggc" option.

    -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=2M

    need to defining NumberOfGClogFiles option will lead to inconsistent JVM options and JVM will not boot like:

    So I try this:

    HBASE_MASTER_OPTS=" -XX:PermSize=64m -XX:MaxPermSize={{hbase_master_maxperm_size}} -Xms{{hbase_heapsize}} -Xmx{{hbase_heapsize}} -Xmn{{hbase_master_xmn_size}} -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=3 -XX:GCLogFileSize=20M" 
.

    NOTE: Also in my case the JVM was not booting because there is a Typo in my case "-XX:NumberOfGClogFiles" (here I used lowercase log) where as the correct option has Uppercase L in the option like "-XX:NumberOfGCLogFiles"