[
https://issues.apache.org/jira/browse/KUDU-2366?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16841185#comment-16841185
]
HeLifu commented on KUDU-2366:
------------------------------
Maybe we can refer to redis's operation for dict rehash which could expand and
shrink. :)
> LockManager consumes significant memory
> ---------------------------------------
>
> Key: KUDU-2366
> URL: https://issues.apache.org/jira/browse/KUDU-2366
> Project: Kudu
> Issue Type: Improvement
> Components: tablet
> Affects Versions: 1.7.0
> Reporter: Todd Lipcon
> Assignee: Todd Lipcon
> Priority: Major
>
> Looking at a heap dump of a server that's been running for a while with an
> ingest workload across multiple tables, I see the LockManager is using about
> 200MB of RAM. The workload in this case has batches of about 30,000 rows
> each, so while each batch is in flight the LockManager hashtable has that
> many locks in it. That causes it to expand to the next higher power of two
> (64k slots). Each slot takes 16 bytes, so the lock table is reaching about
> 1MB. We never resize _down_, so even once the tablet becomes cold, it still
> uses 1M of unrecoverable RAM for the rest of the tserver lifetime.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
