BloomFilterFalsePositives equals 1.0

[Preston Chang <zh...@gmail.com>]

Hi,all:
     I have a problem with bloom filter. When made a test which tried to get
some nonexistent keys, it seemed that the bloom filter does not work. The
'BloomFilterFalseRatio' was 1.0 and the 'BloomFilterFalsePositives' was
rising and the disk I/O utils reached 100% according to 'iostat'.

    I found the patch in
https://issues.apache.org/jira/browse/CASSANDRA-2637 , but in my cluster key
cache had been enabled already.  My Cassandra version is 0.7.3. There are 3
nodes and RF is 3.

    Thanks for your help.

-- 
by Preston Chang

Re: BloomFilterFalsePositives equals 1.0

[Chris Burroughs <ch...@gmail.com>]

To be precise, you made n requests for non-existent keys, got n negative
responses, and BloomFilterFalsePositives also went up by n?

On 06/21/2011 11:06 PM, Preston Chang wrote:
> Hi,all:
>      I have a problem with bloom filter. When made a test which tried to get
> some nonexistent keys, it seemed that the bloom filter does not work. The
> 'BloomFilterFalseRatio' was 1.0 and the 'BloomFilterFalsePositives' was
> rising and the disk I/O utils reached 100% according to 'iostat'.
> 
>     I found the patch in
> https://issues.apache.org/jira/browse/CASSANDRA-2637 , but in my cluster key
> cache had been enabled already.  My Cassandra version is 0.7.3. There are 3
> nodes and RF is 3.
> 
>     Thanks for your help.
>