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https://issues.apache.org/jira/browse/CASSANDRA-792?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12833657#action_12833657
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Stu Hood commented on CASSANDRA-792:
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> how is this different from existing min/max compaction files? sounds like
> just a rename to me from that quote.
There is one other difference: mergeFactor also determines the size of the
buckets that sstables are compacted in.
> My initial reaction is that this is not something we want to do.
I think we may be forced to. Without throttling writes to a level that
compactions can sustain, you can run into situations where you have many
thousands of sstables on disk, which leads to abysmal read performance. If
people _want_ to be in this situation, then we can allow them to disable
compaction, but otherwise, compaction needs to be able to keep up.
> Configurable 'merge factor' for Column Families
> -----------------------------------------------
>
> Key: CASSANDRA-792
> URL: https://issues.apache.org/jira/browse/CASSANDRA-792
> Project: Cassandra
> Issue Type: New Feature
> Reporter: Stu Hood
> Fix For: 0.6
>
> Attachments:
> 0001-Use-logarithmic-bucket-sizes-and-always-compact-the-.patch,
> 0002-Cap-memory-usage-for-all-SSTables-being-compacted.patch,
> 0003-Hardcoded-per-cf-merge-factor.patch, 0004-Configurable-MergeFactor.patch
>
>
> Apache Lucene flushes and merges 'segments' in a manner that is quite similar
> to the treatment of Cassandra's sstables.
> One interesting and powerful tunable that Lucene provides is 'mergeFactor':
> EDIT: better link:
> http://hudson.zones.apache.org/hudson/job/Lucene-trunk/javadoc/core/org/apache/lucene/index/IndexWriter.html#setMergeFactor(int)
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