I set up RAID0 after experiencing highly imbalanced disk usage with a JBOD setup so my transaction logs are indeed on the same media as the sstables. Is there any alternative to setting up RAID0 that doesn't have this issue?
On Thu, Jul 23, 2015 at 4:03 PM, Jeff Ferland <j...@tubularlabs.com> wrote: > My immediate guess: your transaction logs are on the same media as your > sstables and your OS prioritizes read requests. > > -Jeff > > > On Jul 23, 2015, at 2:51 PM, Soerian Lieve <sli...@liveramp.com> wrote: > > > > Hi, > > > > I am currently performing benchmarks on Cassandra. Independently from > each other I am seeing ~100k writes/sec and ~50k reads/sec. When I read and > write at the same time, writing drops down to ~1000 writes/sec and reading > stays roughly the same. > > > > The heap used is the same as when only reading, as is the disk > utilization. Replication factor is 3, consistency level on both reads and > writes is ONE. Using Cassandra 2.1.6. All cassandra.yaml settings set up > according to the Datastax guide. All nodes are running on SSDs. > > > > Any ideas what could cause this? > > > > Thanks, > > Soerian > >
