Are you doing QUORUM reads instead of LOCAL_QUORUM reads?
On Wed, Oct 9, 2013 at 7:41 PM, Chris Burroughs <chris.burrou...@gmail.com>wrote: > I have not been able to do the test with the 2nd cluster, but have been > given a disturbing data point. We had a disk slowly fail causing a > significant performance degradation that was only resolved when the "sick" > node was killed. > * Perf in DC w/ sick disk: > http://i.imgur.com/W1I5ymL.**png?1<http://i.imgur.com/W1I5ymL.png?1> > * perf in other DC: > http://i.imgur.com/gEMrLyF.**png?1<http://i.imgur.com/gEMrLyF.png?1> > > Not only was a single slow node able to cause an order of magnitude > performance hit in a dc, but the other dc faired *worse*. > > > On 09/18/2013 08:50 AM, Chris Burroughs wrote: > >> On 09/17/2013 04:44 PM, Robert Coli wrote: >> >>> On Thu, Sep 5, 2013 at 6:14 AM, Chris Burroughs >>> <chris.burrou...@gmail.com>**wrote: >>> >>> We have a 2 DC cluster running cassandra 1.2.9. They are in actual >>>> physically separate DCs on opposite coasts of the US, not just logical >>>> ones. The primary use of this cluster is CL.ONE reads out of a single >>>> column family. My expectation was that in such a scenario restarts >>>> would >>>> have minimal impact in the DC where the restart occurred, and no >>>> impact in >>>> the remote DC. >>>> >>>> We are seeing instead that restarts in one DC have a dramatic impact on >>>> performance in the other (let's call them DCs "A" and "B"). >>>> >>>> >>> Did you end up filing a JIRA on this, or some other outcome? >>> >>> =Rob >>> >>> >> >> No. I am currently in the process of taking a 2nd cluster from being >> single to dual DC. Once that is done I was going to repeat the test >> with each cluster and gather as much information as reasonable. >> > >
