[
https://issues.apache.org/jira/browse/HBASE-20914?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16551528#comment-16551528
]
Hudson commented on HBASE-20914:
--------------------------------
Results for branch branch-2.0
[build #573 on
builds.a.o|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.0/573/]:
(/) *{color:green}+1 overall{color}*
----
details (if available):
(/) {color:green}+1 general checks{color}
-- For more information [see general
report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.0/573//General_Nightly_Build_Report/]
(/) {color:green}+1 jdk8 hadoop2 checks{color}
-- For more information [see jdk8 (hadoop2)
report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.0/573//JDK8_Nightly_Build_Report_(Hadoop2)/]
(/) {color:green}+1 jdk8 hadoop3 checks{color}
-- For more information [see jdk8 (hadoop3)
report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.0/573//JDK8_Nightly_Build_Report_(Hadoop3)/]
(/) {color:green}+1 source release artifact{color}
-- See build output for details.
> Trim Master memory usage
> ------------------------
>
> Key: HBASE-20914
> URL: https://issues.apache.org/jira/browse/HBASE-20914
> Project: HBase
> Issue Type: Sub-task
> Components: master
> Reporter: stack
> Assignee: stack
> Priority: Major
> Fix For: 3.0.0, 2.0.2, 2.2.0, 2.1.1
>
> Attachments: HBASE-20914.branch-2.0.001.patch, Screen Shot 2018-07-19
> at 1.20.23 PM.png, Screen Shot 2018-07-19 at 1.20.23 PM.png, Screen Shot
> 2018-07-19 at 1.38.56 PM.png, Screen Shot 2018-07-19 at 1.38.56 PM.png,
> Screen Shot 2018-07-19 at 2.22.42 PM.png, Screen Shot 2018-07-19 at 2.22.42
> PM.png, Screen Shot 2018-07-19 at 2.43.42 PM.png, Screen Shot 2018-07-19 at
> 2.43.42 PM.png
>
>
> While working on the parent issue, looking at a heap from a Master tha was
> running ~650 servers and > 300k regions, I tripped over some silly items in
> the heap:
> 1. Balancer has a regions x server matrix which takes up 18% of the Master
> heap according to jxray and 40% according to eclipse. Looks like the matrix
> should be regions x racks which would be much smaller (Issue came in with
> HBASE-18164 Fast locality computation in balancer -Added new
> LocalityCostFunction and LocalityCandidateGenerator ..). See !Screen Shot
> 2018-07-19 at 1.20.23 PM.png! !Screen Shot 2018-07-19 at 1.38.56 PM.png!
> 2. Duplicate Strings make up ~5% of the Master heap. Of these, ServerName
> seems to be the font. Interesting is report that there 54k instances of
> ServerName in this heap though there are only 650 Servers. See !Screen Shot
> 2018-07-19 at 2.22.42 PM.png!
> 3. ArrayDequeue initializes its internal elements array with 16 elements. We
> use this in a few places. In Procedures, of which there are many in this
> heap, we near never make use of this array. See !Screen Shot 2018-07-19 at
> 2.43.42 PM.png!
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
