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https://issues.apache.org/jira/browse/OAK-5192?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16103259#comment-16103259
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Tommaso Teofili commented on OAK-5192:
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I've done several tests with different parameters of TieredMergePolicy, however
with the 4k inline limit, not much seemed to change size wise.
On the other hand I have started implement one of the first ideas I had to
mitigate this, that is to explicitly avoid merges during high commit rates time
frames, so that it avoid merging unnecessarily.
In a first test this morning (with 4k limit) this made the FDS size go from 2
to 1GB.
I am now performing more thorough tests.
> Reduce Lucene related growth of repository size
> -----------------------------------------------
>
> Key: OAK-5192
> URL: https://issues.apache.org/jira/browse/OAK-5192
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: lucene, segment-tar
> Reporter: Michael Dürig
> Assignee: Tommaso Teofili
> Labels: perfomance, scalability
> Fix For: 1.8, 1.7.8
>
> Attachments: added-bytes-zoom.png, binSize100.txt, binSize16384.txt,
> binSizeTotal.txt, diff.txt.zip, nonBinSizeTotal.txt, OAK-5192.0.patch, Screen
> Shot 2017-07-03 at 16.50.00.png
>
>
> I observed Lucene indexing contributing to up to 99% of repository growth.
> While the size of the index itself is well inside reasonable bounds, the
> overall turnover of data being written and removed again can be as much as
> 99%.
> In the case of the TarMK this negatively impacts overall system performance
> due to fast growing number of tar files / segments, bad locality of
> reference, cache misses/thrashing when looking up segments and vastly
> prolonged garbage collection cycles.
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