Hi Yemin, what kind of tests are used in the YCSB? Are you using the Java driver from ArangoDB or direct HTTP requests? Sometimes I have seen, that in various languages HTTP are not persistent (by default or at all). Could you see during your test, if there are persistent HTTP connections or not?
A dispatcher thread keeps active for a few milli-seconds, before waiting on a condition variable. This gives better performance on some systems comapred to directly going to sleep. Best Am Mittwoch, 4. Mai 2016 17:17:17 UTC+2 schrieb Yemin: > > Hi, recently I'm doing perf test of ArangoDB using YCSB and found > the dispatcher threads problems. > Case: pure inserting operations, measuring throughput. 10 scheduler > threads, 48 clients. > For throughput and total CPU cost of dispatcher threads, one dispatcher > thread has no difference with multiple dispatcher threads. It looks like > there is some kind of "global lock". > Questions: > 1. Why the throughput wasn't improved by adding more dispatcher threads. > 2. We found many nanosleeps in dispatcher thread, maybe it's one of > reasons? And why using nanosleep instead of wait-signal? > > Thx! > -- You received this message because you are subscribed to the Google Groups "ArangoDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
