> Actually when I run 2 stress clients in parallel I see Read Latency stay the > same. I wonder if cassandra is reporting accurate nos.
Or you're just bottlenecking on something else. Are you running the extra stress client on different machines for example, so that the client isn't just saturating? > I understand your analogy but for some reason I don't see that happening > with the results I am seeing with multiple stress clients running. So I am > just confused where the real bottleneck is. If your queue size to your device is consistently high (you were mentioning numbers in the ~100 range), you're saturating on disk, periods. Unless your disk is a 500 drive RAID volume and 100 requests represents 1/5 of capacity... (If you have a raid volume with a few disks or an ssd, you want to switch to the noop or deadline scheduler btw.) -- / Peter Schuller
