Alta, The RowsCached attribute can take an integer, percentage or, like KeysCachedFraction, a value between 0 and 1. I had a good idea already how many records where going to be hot for the CF I was using to test, show just matching that to available JVM memory was pretty straight forward.
There was other stuff going on with the machine I was using to test this with, so I would be interested to here from anybody else who had dedicated hardware what sort of numbers they got over just relying on a lot of ram and file system caching. Cheers, -Nate On Wed, Feb 3, 2010 at 1:15 AM, envio user <enviou...@gmail.com> wrote: > Hi Nate, > > On Wed, Feb 3, 2010 at 12:31 AM, Nathan McCall <n...@vervewireless.com> wrote: >> Thank you for the benchmarks. What version of Cassandra are you using? > I am using 0.5 release. >> I had about 80% performance improvement on single node reads after >> using a trunk build with the results from >> https://issues.apache.org/jira/browse/CASSANDRA-688 (result caching) >> and playing around with the configuration. I am not yet running this >> in production though, so I cannot provide any real numbers. >> > Do you any specific config parameters needs to be used for this purpose? > >> That said, I have no intention of deploying a single node. I keep >> seing performance concerns from folks on small or single node >> clusters. My impression so far is that Cassandra may not be the right >> solution for these types of deployments. > > As part of evaluation we are testing cassandra with single node. I > agree for deployment it is not good having just single node. > > <<snip>> >> >> What I found to have been most valuable for my evaluation was to get a >> good test together with some real data from our system and then add >> nodes, remove nodes, break nodes, etc. and watch what happens. Once I >> finish with this, it looks like I will have some solid numbers to do >> some capacity planning for figuring out exactly how much hardware to >> purchase and when I will need to add more. > We are just doing some basic tests. If cassandra passes these tests, > may be we will do tests you mentioned later. > > thanks, > -Aita >
