Are you writing these records as batches (with begin batch, not begin
unlogged)? As a logged batch ('begin batch' is logged) gets written to a
system keyspace with CL before being applied to the underlying CF, and I'm
not sure we want to go special casing that for non-durable writes, since
you probably should just be using unlogged batches if you don't care.On 27 March 2014 15:28, Keith Freeman <8fo...@gmail.com> wrote: > We're running an insert-heavy use-case and have set "durable_writes = > false" for all of our keyspaces. While inserts are coming in (about 2000 > 1k-records per second), we are still seeing 50Mb written to files in the > commitlog directory every 6-10 seconds (using iostat). > > Anybody know why so much data would written in this situation? We're > guessing that these writes are related to the system and system_traces > keyspaces, right? Is it considered ok to turn off durable_writes on those > keyspaces? (I couldn't find anything on this searching the message board > or google). > > (Note we have double- and triple- checked that all of our keyspaces > definitely have durable_writes=false, with multiple clean-and-restarts of > cassandra) > >
