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Ophir Radnitz commented on CASSANDRA-3497:
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We've tried this patch with 1.0.6 with fp_ratio of 0.99 (if I get it correctly,
after a major compaction and a single albeit large SSTable, bloom filter has
very little effect). We've found that many records that were inserted counld
not be fetched in a multiget_slice query. It seemed as if the bloom filters
resulted in *false negatives*.
By the way, the fix patch (0001-give-default-val-to-fp_chance.patch) works for
the 1.1 branch but not for 1.0.
> BloomFilter FP ratio should be configurable or size-restricted some other way
> -----------------------------------------------------------------------------
>
> Key: CASSANDRA-3497
> URL: https://issues.apache.org/jira/browse/CASSANDRA-3497
> Project: Cassandra
> Issue Type: New Feature
> Components: Core
> Reporter: Brandon Williams
> Assignee: Yuki Morishita
> Priority: Minor
> Fix For: 1.0.7
>
> Attachments: 0001-give-default-val-to-fp_chance.patch, 3497-v3.txt,
> 3497-v4.txt, CASSANDRA-1.0-3497.txt
>
>
> When you have a live dc and purely analytical dc, in many situations you can
> have less nodes on the analytical side, but end up getting restricted by
> having the BloomFilters in-memory, even though you have absolutely no use for
> them. It would be nice if you could reduce this memory requirement by tuning
> the desired FP ratio, or even just disabling them altogether.
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