>> Are you experiencing memory pressure you think may be attributed to >> memtables not being flushed frequently enough ? > Try reducing memtable_total_space_in_mb config setting. If the problem is incorrect memory metering that should help.
> i have 3 workload types running in batch. Delete only workload, insert only > and heavy update (lot of overwrites) Are you saying you do a lot of deletes, followed by a lot of inserts and then updates all for the same CF ? > yes. Record is about 120, but it is rare. 80 should be good enough. Default > 10 (if not jusing jamm) is way too low. Can you provide some information on what is stored in the CF and what sort of workload. It would be interesting to understand why the real memory usage is 120 times the serialised size. Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 15/05/2012, at 1:50 AM, Radim Kolar wrote: > > liveratio calculation logic also needs to be changed because it is based on > assumption that workloads do not change. >> Can you give an example of the sort of workload change you are thinking of ? > i have 3 workload types running in batch. Delete only workload, insert only > and heavy update (lot of overwrites) > >>> raise maximum liveratio from 64 to at least 80. >> Have you seen examples in your logs where the calculated live ratio was >> between 64 and 80 ? > yes. Record is about 120, but it is rare. 80 should be good enough. Default > 10 (if not jusing jamm) is way too low. >> Are you experiencing memory pressure you think may be attributed to >> memtables not being flushed frequently enough ? > yes
