Hi all - first timer here. I'm experimenting with Cassandra on Rackspace Cloud. Started with 4GB nodes and saw read latency spikes while streaming was taking place, so I increased to 8GB to see if limited memory was the issue. Now I'm seeing very strange behavior during any period that writes are taking place. The entire (6 node) cluster seems to pause for periods of as much as 5-8 sec. By that I mean all the stats (cpu, disk, network IO monitored via dstat) drop to zero or near zero on all nodes simultaneously. Does anyone have experience with Cassandra on Rackspace or any idea what's going on here?
The pauses are short enough that it's difficult to introspect the application and determine what it's doing during the pause, but long enough to cause unacceptable latency for any service built on top of it. Any ideas or debugging methods would be greatly appreciated, -- Oren
