weird problem with performance

2011-10-19 Thread Yang
I'm using a cassandra version compiled from 1.0.0 github HEAD. I have 3 nodes, A B and C, on node A I run a client, which talks only to B as the coordinator. the performance is pretty good, a QUORUM read+write takes < 10ms. but then I shutdown C, quickly the performance starts to degrade, and

Re: weird problem with performance

2011-10-19 Thread Jérémy SEVELLEC
Hi, what is your replication_factor? 2011/10/19 Yang > I'm using a cassandra version compiled from 1.0.0 github HEAD. > > I have 3 nodes, A B and C, on node A I run a client, which talks only > to B as the coordinator. > > the performance is pretty good, a QUORUM read+write takes < 10ms. > >

Re: weird problem with performance

2011-10-19 Thread Yang
3 sorry forgot this important info On Oct 19, 2011 11:31 AM, "Jérémy SEVELLEC" wrote: > Hi, what is your replication_factor? > > 2011/10/19 Yang > >> I'm using a cassandra version compiled from 1.0.0 github HEAD. >> >> I have 3 nodes, A B and C, on node A I run a client, which talks only >> t

Re: weird problem with performance

2011-10-19 Thread Jérémy SEVELLEC
Ok. I think a degration could be normal because your cluster is in a degraded state when a node is down. With a replication_factor of 3 and with a 3 nodes cluster, each data you write is replicated on each node. As One node is down, when writing, it's impossible to send a replica on the down node

Re: weird problem with performance

2011-10-20 Thread aaron morton
It's unlikely that HH is the issue. (Disclaimer, am not familiar with HH in 1.0, i know it's changes a bit) Take a look at the TP Stats, what's happening ? Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 20/10/2011, at 10:10 AM, Jérémy SEV

Re: weird problem with performance

2011-10-20 Thread Yang
found it , https://issues.apache.org/jira/browse/CASSANDRA-3387 On Thu, Oct 20, 2011 at 1:37 PM, aaron morton wrote: > It's unlikely that HH is the issue. (Disclaimer, am not familiar with HH in > 1.0, i know it's changes a bit) > Take a look at the TP Stats, what's happening ? > Cheers > ---

Re: weird problem with performance

2011-10-21 Thread Jérémy SEVELLEC
@Araron you're right and i was wrong! 2011/10/20 Yang > found it , https://issues.apache.org/jira/browse/CASSANDRA-3387 > > On Thu, Oct 20, 2011 at 1:37 PM, aaron morton > wrote: > > It's unlikely that HH is the issue. (Disclaimer, am not familiar with HH > in > > 1.0, i know it's changes a bit

Re: weird problem with performance

2011-10-21 Thread Yang
actually this is only an issue in HH, since HH writes all the stored messages into the same row, so locking is a problem 2011/10/21 Jérémy SEVELLEC : > @Araron you're right and i was wrong! > > 2011/10/20 Yang >> >> found it , https://issues.apache.org/jira/browse/CASSANDRA-3387 >> >> On Thu, Oct