Yeah, disabling completely is probably not great. There is some wriggle room between disabled and "less memory"
Did I link to this bloom filter calculator ? http://hur.st/bloomfilter also https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/utils/BloomCalculations.java Cheers ----------------- Aaron Morton Freelance Cassandra Developer New Zealand @aaronmorton http://www.thelastpickle.com On 23/02/2013, at 12:10 PM, Bryan Talbot <btal...@aeriagames.com> wrote: > I see from your read and write count that your nreldata CF has nearly equal > number of reads as writes. I would expect that disabling your bloom filter > is going to hurt your read performance quite a bit. > > Also, beware that disabling your bloom filter may also cause tombstoned rows > to never be deleted, so if you delete all columns explicitly or use TTL, your > data may grow more than your expect. > https://issues.apache.org/jira/browse/CASSANDRA-5182 > > -Bryan > > > > > On Fri, Feb 22, 2013 at 11:59 AM, Hiller, Dean <dean.hil...@nrel.gov> wrote: > Thanks, but I found out it is still running. It looks like I have about a 5 > hour wait left for my upgradesstables(waited 4 hours already). I will check > the bloomfilter after that. > > Out of curiosity, if I had much wider rows (ie. < 900k) per row, will > compaction run faster(errrr…upgradesstables) at all or would it basically run > at the same speed. > > I guess what I am wondering is 9 hours a normal compaction time for 130gb of > data? > > Thanks, > Dean > > From: aaron morton <aa...@thelastpickle.com<mailto:aa...@thelastpickle.com>> > Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" > <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> > Date: Friday, February 22, 2013 10:29 AM > To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" > <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> > Subject: Re: disabling bloomfilter not working? or did I do this wrong? > > Bloom Filter Space Used: 2318392048 > Just to be sane do a quick check of the -Filter.db files on disk for this CF. > If they are very small try a restart on the node. > > Number of Keys (estimate): 1249133696 > Hey a billion rows on a node, what an age we live in :) > > Cheers > > ----------------- > Aaron Morton > Freelance Cassandra Developer > New Zealand > > @aaronmorton > http://www.thelastpickle.com > > On 23/02/2013, at 4:35 AM, "Hiller, Dean" > <dean.hil...@nrel.gov<mailto:dean.hil...@nrel.gov>> wrote: > > So in the cli, I ran > > update column family nreldata with bloom_filter_fp_chance=1.0; > > Then I ran > > nodetool upgradesstables databus5 nreldata; > > But my bloom filter size is still around 2gig(and I want to free up this > heap)!!!! According to nodetool cfstats command… > > Column Family: nreldata > SSTable count: 10 > Space used (live): 96841497731 > Space used (total): 96841497731 > Number of Keys (estimate): 1249133696 > Memtable Columns Count: 7066 > Memtable Data Size: 4286174 > Memtable Switch Count: 924 > Read Count: 19087150 > Read Latency: 0.595 ms. > Write Count: 21281994 > Write Latency: 0.013 ms. > Pending Tasks: 0 > Bloom Filter False Postives: 974393 > Bloom Filter False Ratio: 0.99998 > Bloom Filter Space Used: 2318392048 > Compacted row minimum size: 73 > Compacted row maximum size: 446 > Compacted row mean size: 143 > > > > >
