cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From aaron morton <aa...@thelastpickle.com>
Subject Re: Counter consistency - are counters idempotent?
Date Sun, 24 Jul 2011 22:36:51 GMT
What's your use case ? There are people out there having good times with counters, see

http://www.slideshare.net/kevinweil/rainbird-realtime-analytics-at-twitter-strata-2011
http://www.scribd.com/doc/59830692/Cassandra-at-Twitter

Cheers

-----------------
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com

On 23 Jul 2011, at 08:37, Aaron Turner wrote:

> On Fri, Jul 22, 2011 at 9:27 AM, Donal Zang <zangds@ihep.ac.cn> wrote:
>> On 22/07/2011 18:08, Yang wrote:
>>> 
>>> btw, this "issue" of  not knowing whether a write is persisted or not
>>> when client reports error, is not limited to counters,  for regular
>>> columns, it's the same: if client reports write failure, the value may
>>> well be replicated to all replicas later.  this is even the same with
>>> all other systems: Zookeeper, Paxos, ultimately due to the FLP
>>> theoretical result of "no guarantee of consensus in async systems"
>> 
>> yes, but with regular columns, retry is OK, while counter is not.
> 
> I know I've heard that fixing this issue is "hard".  I've assumed this
> to mean "don't expect a fix anytime soon".  Is that accurate?
> Beginning to start having second thoughts that Cassandra is the right
> fit for my project which would heavily rely on counters to roll up
> aggregates.
> 
> -- 
> Aaron Turner
> http://synfin.net/         Twitter: @synfinatic
> http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & Windows
> Those who would give up essential Liberty, to purchase a little temporary
> Safety, deserve neither Liberty nor Safety.
>     -- Benjamin Franklin
> "carpe diem quam minimum credula postero"


Mime
View raw message