On 2014-02-23 20:04:39 +0100, Pavel Stehule wrote: > There is relative few very long ProcArrayLocks lwlocks > > This issue is very pathologic on fast computers with more than 8 CPU. This > issue was detected after migration from 8.4 to 9.2. (but tested with same > result on 9.0) I see it on devel 9.4 today actualized. > > When I moved PREPARE from cycle, then described issues is gone. But when I > use a EXECUTE IMMEDIATELY, then the issue is back. So it looks it is > related to planner, ...
In addition to the issue Jeff mentioned, I'd suggest trying the same workload with repeatable read. That can do *wonders* because of the reduced number of snapshots.
I tested it, and it doesn't help.
Is there some patch, that I can test related to this issue?
Greetings,
Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
