> Its in the order of 261 to 8000 and the ratio is 0.00. But i guess 8000 is > bit high. Is there a way to fix/improve it? Sorry I don't understand what you mean. But if the ratio is 0.0 all is good.
Could you include the full output from cfstats for the CF you are looking at ? Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 15/02/2012, at 1:00 PM, Eran Chinthaka Withana wrote: > Its in the order of 261 to 8000 and the ratio is 0.00. But i guess 8000 is > bit high. Is there a way to fix/improve it? > > Thanks, > Eran Chinthaka Withana > > > On Tue, Feb 14, 2012 at 3:42 PM, aaron morton <aa...@thelastpickle.com> wrote: > Out of interest what does cfstats say about the bloom filter stats ? A high > false positive could lead to a low key cache hit rate. > >> Also, is there a way to warm start the key cache, meaning pre-load the >> amount of keys I set as keys_cached? > > See key_cache_save_period when creating the CF. > > Cheers > > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 15/02/2012, at 5:54 AM, Eran Chinthaka Withana wrote: > >> Hi, >> >> I'm using Cassandra 1.0.7 and I've set the keys_cached to about 80% (using >> the numerical values). This is visible in cfstats too. But I'm getting less >> than 20% (or sometimes even 0%) key cache hit rate. Well, the data access >> pattern is not the issue here as I know they are retrieving the same row >> multiple times. I'm using hector client with dynamic load balancing policy >> with consistency ONE for both reads and writes. Any ideas on how to find the >> issue and fix this? >> >> Here is what I see on cfstats. >> >> Key cache capacity: 16637958 >> Key cache size: 16637958 >> Key cache hit rate: 0.045454545454545456 >> >> Also, is there a way to warm start the key cache, meaning pre-load the >> amount of keys I set as keys_cached? >> >> Thanks, >> Eran > >
