jackrabbit-oak-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Michael Dürig (JIRA) <j...@apache.org>
Subject [jira] [Commented] (OAK-4635) Improve cache eviction policy of the node deduplication cache
Date Mon, 08 Aug 2016 14:30:20 GMT

    [ https://issues.apache.org/jira/browse/OAK-4635?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15411879#comment-15411879
] 

Michael Dürig commented on OAK-4635:
------------------------------------

I updated both branches from above with an approach where evicting a random element from the
cache doesn't suffer the performance penalty seen so far:

* https://github.com/mduerig/jackrabbit-oak/tree/OAK-4635-1: evict single element on deepest
level instead of entire level
* https://github.com/mduerig/jackrabbit-oak/tree/OAK-4635-2: cache nodes by weight instead
of depth

> Improve cache eviction policy of the node deduplication cache
> -------------------------------------------------------------
>
>                 Key: OAK-4635
>                 URL: https://issues.apache.org/jira/browse/OAK-4635
>             Project: Jackrabbit Oak
>          Issue Type: Improvement
>          Components: segment-tar
>            Reporter: Michael Dürig
>            Assignee: Michael Dürig
>              Labels: perfomance
>             Fix For: Segment Tar 0.0.10
>
>
> {{NodeCache}} uses one stripe per depth (of the nodes in the tree). Once its overall
capacity (default 1000000 nodes) is exceeded, it clears all nodes from the stripe with the
greatest depth. This can be problematic when the stripe with the greatest depth contains most
of the nodes as clearing it would result in an almost empty cache. 



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message