Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile

On Sat, 26 May 2012, Robert Haas wrote:
> This theory is seeming fairly plausible - how can we test it?
>
> How about trying it with synchronize_seqscans = off?  If the
> synchronized-seqscan logic is causing contention on the buf mapping
> locks and individual buffer locks, that should fix it.

Turning off synch seq scans doesn't help either. 18 sec multithreaded run 
vs 7 sec single threaded.
    S

*****************************************************
Sergey E. Koposov, PhD, Research Associate
Institute of Astronomy, University of Cambridge
Madingley road, CB3 0HA, Cambridge, UK
Tel: +44-1223-337-551 Web: http://www.ast.cam.ac.uk/~koposov/