Hi, I have a performance problem related to my use of multiple ColumnFamilies. Maybe there's a better way to represent my data such that I don't hit this problem, I don't know, but as things stand, I'm putting data into each ColumnFamily at a rate which is more-or-less the same for each. This means that each ColumnFamily crosses the memtable-to-sstable threshold at approximately the same time - but Cassandra only has one thread which writes memtables to disk, so the observed behaviour is that ColumnFamilies start waiting for each other to be written to disk, but will not accept new inserts until this has happened, which leads to time-outs for both reads and writes.
Can anyone confirm whether or not this behaviour is expected, and suggest anything that I could do about it? This is on 0.6.6, by the way. Patched with time-to-live code, if that makes a difference. Thanks, Andy. -- Andy Burgess Principal Development Engineer Application Delivery WorldPay Ltd. 270-289 Science Park, Milton Road Cambridge, CB4 0WE, United Kingdom (Depot Code: 024) Office: +44 (0)1223 706 779| Mobile: +44 (0)7909 534 940 andy.burg...@worldpay.com
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