incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Robin Verlangen <ro...@us2.nl>
Subject Re: are counters stable enough for production?
Date Tue, 18 Sep 2012 07:30:27 GMT
@Rohit: We also use counters quite a lot (lets say 2000 increments / sec),
but don't see the 50-100KB of garbage per increment. Are you sure that
memory is coming from your counters?

Best regards,

Robin Verlangen
*Software engineer*
*
*
W http://www.robinverlangen.nl
E robin@us2.nl

Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
confidential. If you are not the intended recipient, you are reminded that
the information remains the property of the sender. You must not use,
disclose, distribute, copy, print or rely on this e-mail. If you have
received this message in error, please contact the sender immediately and
irrevocably delete this message and any copies.



2012/9/18 rohit bhatia <rohit2412@gmail.com>

> We use counters in a 8 node cluster with RF 2 in cassandra 1.0.5.
> We use phpcassa and execute cql queries through thrift to work with
> composite types.
>
> We do not have any problem of overcounts as we tally with RDBMS daily.
>
> It works fine but we are having some GC pressure for young generation.
> Per my calculation around 50-100 KB of garbage is generated every
> counter increment.
> Is this memory usage expected of counters?
>
> On Tue, Sep 18, 2012 at 7:16 AM, Bartłomiej Romański <br@sentia.pl> wrote:
> > Hi,
> >
> > Does anyone have any experience with using Cassandra counters in
> production?
> >
> > We rely heavily on them and recently we've got a few very serious
> > problems. Our counters values suddenly became a few times higher than
> > expected. From the business point of view this is a disaster :/ Also
> > there a few open major bugs related to them. Some of them for quite
> > long (months).
> >
> > We are seriously considering going back to other solutions (e.g. SQL
> > databases). We simply cannot afford incorrect counter values. We can
> > tolerate loosing a few increments from time to time, but we cannot
> > tolerate having counters suddenly 3 times higher or lower than the
> > expected values.
> >
> > What is the current status of counters? Should I consider them a
> > production-ready feature and we just have some bad luck? Or should I
> > rather consider them as a experimental-feature and look for some other
> > solutions?
> >
> > Do you have any experiences with them? Any comments would be very
> > helpful for us!
> >
> > Thanks,
> > Bartek
>

Mime
View raw message