Try doing request tracing. http://www.datastax.com/dev/blog/tracing-in-cassandra-1-2
On Thu, Jun 27, 2013 at 2:40 PM, Bao Le <l...@yahoo.com> wrote: > Hi, > > We are using Leveled Compaction with Cassandra 1.2.5. Our sstable size > is 100M. On each node, > we have anywhere from 700+ to 800+ sstables (for all levels). The > bloom_filter_fp_chance is set at 0.000744. > > For read requests that ask for existing row records, the latency is > great, mostly under 20 milliseconds with key cache and row cache set. For > read requests that ask for non-existing row records (not because of > deletes, but rather, have never been in the system to start with), the > latency is running into hundreds of milliseconds and sometimes seconds. > > Just wonder if anyone has come across this before and has some pointers > on how to reduce the latency in this case. > > Thanks > Bao > > > >
