Hi, ZK uses a quorum protocol (similar but not the same as paxos) for
writes, as a result it's sensitive to inter-server latency. (however
reads are always local and therefore not effected) Running a cluster
fully w/in a colo you can achieve 15k writes/second, with a cluster
distributed across a wan the write performance will be lower. You can
see some detail on in-colo performance here http://bit.ly/4B8gC7 and
here http://bit.ly/4ekN8G
Regards,
Patrick
On 05/16/2010 07:10 PM, Chris Goffinet wrote:
If you are running multiple datacenters, intend to have a lot of writes for
counters, I highly advise against it. We got rid of ZK because of that.
-Chris
On May 16, 2010, at 7:04 PM, S Ahmed wrote:
Can someone quickly go over how you go about using zookeeper if you want to
store counts and have those counts be accurate?
e.g. in digg's case I believe, they are using zookeeper so they can keep track
of digg's for a particular digg story.
Is it a backend change only and then storing API calls are uneffected? is it a
config issue ?
What are the ramifications of using this addon, are writes slower because you
have to wait for the write to propogate to all the servers?
