Re: Read latency issue

2012-10-03 Thread Sergey Tryuber
Hi Arindam, Just want to share our experience about latency. We use Cassandra to read all columns for a specified key (5-10 columns, 10-15 each, no composites). All our dataset fits memory (40GB on each node) and we use LeveledCompactionStrategy. Our RF=2 and we read with CL=ONE. Also we use Astya

Re: Nodetool repair and Leveled Compaction

2012-09-24 Thread Sergey Tryuber
Hi Radim Unfortunately number of compaction tasks is not overestimated. The number is decremented one-by-one and this process takes several hours for our 40GB node(( Also, when a lot of compaction tasks appears, we see that total disk space used (via JMX) is doubled and Cassandra really tries to c

Nodetool repair and Leveled Compaction

2012-09-24 Thread Sergey Tryuber
Hi Guys We've noticed a strange behavior on our 3-nodes staging Cassandra cluster with RF=2 and LeveledCompactionStrategy. When we run "nodetool repair -pr" on a node, the other nodes start "validation" process and when this process is finished one of the other 2 nodes reports that there are app

Re: Long-life TTL and extending TTL

2012-09-15 Thread Sergey Tryuber
Hi Robin, We have the same headache and hope that https://issues.apache.org/jira/browse/CASSANDRA-3974 will be a balsam. On 10 September 2012 13:47, Robin Verlangen wrote: > Hi there, > > I'm working on a project that might want to set TTL to roughly 7 years. > However it might occur that the T

Re: Schema consistently not propagating to a node.

2012-09-13 Thread Sergey Tryuber
Hi Ben, We've seen similar behavior once a time. The cause was unsynchronized time on the nodes. So I can recommend to check that system time is equal over the nodes (especially on that one "bad" server). On 13 September 2012 05:15, Ben Frank wrote: > Hey all, >I'm setting up a new ring on

Re: Replication factor 2, consistency and failover

2012-09-12 Thread Sergey Tryuber
accept reduced consistency > for high availability" rather than say "in general we want to achieve > strong consistency". > > Hope that helps. > > --------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > &g

Replication factor 2, consistency and failover

2012-09-09 Thread Sergey Tryuber
Hi We have to use Cassandra with RF=2 (don't ask why...). There are two datacenters (RF=2 in each datacenter). Also we use Astyanax as a client library. In general we want to achieve strong consistency. Read performance is important for us, that's why we perform writes with LOCAL_QUORUM and reads