> Tatsuo Ishii <ishii@xxxxxxxxxxxx> writes: > > Interesting. We (some Japanese companies including SRA OSS, > > Inc. Japan) did some PG scalability testing using a Unisys's big 16 > > (physical) CPU machine and found PG scales up to 8 CPUs. However > > beyond 8 CPU PG does not scale anymore. The result can be viewed at > > "OSS iPedia" web site (http://ossipedia.ipa.go.jp). Our conclusion was > > PG has a serious lock contention problem in the environment by > > analyzing the oprofile result. > > 18% in s_lock is definitely bad :-(. Were you able to determine which > LWLock(s) are accounting for the contention? Yes. We were interested in that too. Some people did addtional tests to determin that. I don't have the report handy now. I will report back next week. > The test case seems to be spending a remarkable amount of time in LIKE > comparisons, too. That probably is not a representative condition. I know. I think point is 18% in s_lock only appears with 12 CPUs or more. -- Tatsuo Ishii SRA OSS, Inc. Japan
