Hi,
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.
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services