Hi, On 2016-08-22 20:32:42 +0300, Heikki Linnakangas wrote: > I ran some quick pgbench tests on my laptop, but didn't see any meaningful > benefit. I think the best I could see is about 5% speedup, when running > "pgbench -S", with 900 idle connections sitting in the background. On the > positive side, I didn't see much slowdown either. (Sorry, I didn't record > the details of those tests, as I was testing many different options and I > didn't see a clear difference either way.)
Hm. Does the picture change if those are idle in transaction, after assigning an xid. > It seems that Amit's PGPROC batch clearing patch was very effective. It usually breaks down if you have a mixed read/write workload - might be worthehile prototyping that. > I > remember seeing ProcArrayLock contention very visible earlier, but I can't > hit that now. I suspect you'd still see contention on bigger hardware, > though, my laptop has oly 4 cores. I'll have to find a real server for the > next round of testing. Yea, I think that's true. I can just about see ProcArrayLock contention on my more powerful laptop, to see it really bad you need bigger hardware / higher concurrency. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
