By the way, I wonder if a rolling restart is still possible when I am using counters ? Don't we lose the SPOF too, considering that counters are wrong every time we retry to write them with the client ?
2011/12/16 Alain RODRIGUEZ <arodr...@gmail.com> > Can we have a hope that counters will be replayed as safely as a classical > data someday ? Do someone still work on jiras like > issues.apache.org/jira/browse/CASSANDRA-2495 ? I thought that replaying a > write from the client didn't lead to over-counts contrary to the internal > cassandra replay from commitlog. > > I just made a new connection pool with retries / 2 and timeouts * 4. I > hope it will improve the accuracy of my counters. > > Anyways, thank you for answering that fast. > > Alain > > 2011/12/16 Tyler Hobbs <ty...@datastax.com> > >> Probably quite a few of them are coming from automatic retries by >> phpcassa. When working with counters, I recommend minimizing retries >> and/or increasing timeouts. Usually this means you want to use a separate >> connection pool with different settings just for counters. >> >> By the way, this advice applies to other clients as well. >> >> >> On Wed, Dec 14, 2011 at 10:29 AM, Alain RODRIGUEZ <arodr...@gmail.com>wrote: >> >>> Hi everybody. >>> >>> I'm using a lot of counters to make statistics on a 4 nodes cluster (ec2 >>> m1.small) with phpcassa (cassandra v1.0.2). >>> >>> I store some events and increment counters at the same time. >>> >>> Counters give me over-counts compared with the count of every >>> corresponding events. >>> >>> I sure that my non-counters counts are good. >>> >>> I'm not sure why these over-counts happen, but I heard that recovering >>> from commitlogs can produce this. >>> I have some timeouts on phpcassa which are written in my apache logs >>> while a compaction is running. However I am always able to write at Quorum, >>> so I guess I shouldn't have to recover from cassandra commitlogs. >>> >>> Where can these over-counts come from ? >>> >>> Alain >>> >>> >> >> >> >> -- >> Tyler Hobbs >> DataStax <http://datastax.com/> >> >> >
