That does not measure what the servers are doing though. Track the number of reads per CF, it's exposed with nodetool cfstats and is in ops centre as well.
Cheers ----------------- Aaron Morton Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 24/07/2013, at 12:22 AM, Omar Shibli <o...@eyeviewdigital.com> wrote: > I simply monitor the load avg of the nodes using opscenter. > I started with idle nodes (by idle I mean load avg of all nodes < 1.0), then > started to run a lot of key slice read requests on "analytic" DC with CL > local quorum (I also made sure that the client worked with only with analytic > DC), after a few minutes I noticed that the load avg of all the nodes > increased dramatically (>10). > > Thanks in Advance Aaron, > > On Tue, Jul 23, 2013 at 12:02 PM, aaron morton <aa...@thelastpickle.com> > wrote: > > All the read/write request are issued with CL local quorum, but still > > there're a lot of inter-dc read request. > > > How are you measuring this ? > > Cheers > > ----------------- > Aaron Morton > Cassandra Consultant > New Zealand > > @aaronmorton > http://www.thelastpickle.com > > On 22/07/2013, at 8:41 AM, sankalp kohli <kohlisank...@gmail.com> wrote: > > > Slice query does not trigger background read repair. > > Implement Read Repair on Range Queries > > > > > > On Sun, Jul 21, 2013 at 1:40 PM, sankalp kohli <kohlisank...@gmail.com> > > wrote: > > There can be multiple reasons for that > > 1) Background read repairs. > > 2) Your data is not consistent and leading to read repairs. > > 3) For writes, irrespective of the consistency used, a single write request > > will goto other DC > > 4) You might be running other nodetools commands like repair. > > read_repair_chance¶ > > > > (Default: 0.1 or 1) Specifies the probability with which read repairs > > should be invoked on non-quorum reads. The value must be between 0 and 1. > > For tables created in versions of Cassandra before 1.0, it defaults to 1. > > For tables created in versions of Cassandra 1.0 and higher, it defaults to > > 0.1. However, for Cassandra 1.0, the default is 1.0 if you use CLI or any > > Thrift client, such as Hector or pycassa, and is 0.1 if you use CQL. > > > > > > > > On Sun, Jul 21, 2013 at 10:26 AM, Omar Shibli <o...@eyeviewdigital.com> > > wrote: > > One more thing, I'm doing a lot of key slice read requests, is that > > supposed to change anything? > > > > > > On Sun, Jul 21, 2013 at 8:21 PM, Omar Shibli <o...@eyeviewdigital.com> > > wrote: > > I'm seeing a lot of inter-dc read requests, although I've followed DataStax > > guidelines for multi-dc deployment > > http://www.datastax.com/dev/blog/deploying-cassandra-across-multiple-data-centers > > > > Here is my setup: > > 2 data centers within the same region (AWS) > > Targeting DC, RP 3, 6 nodes > > Analytic DC, RP 3, 11 nodes > > > > All the read/write request are issued with CL local quorum, but still > > there're a lot of inter-dc read request. > > Any suggestion, or am I missing something? > > > > Thanks in advance, > > > > > > > >
