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
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