From owner-freebsd-performance@FreeBSD.ORG  Mon Nov 22 08:37:23 2010
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Date: Mon, 22 Nov 2010 16:37:26 +0000
From: David Xu <davidxu@freebsd.org>
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To: Mark Felder <feld@feld.me>
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Cc: freebsd-performance@freebsd.org
Subject: Re: PostgreSQL performance scaling
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Mark Felder wrote:
> I recommend posting this on the Postgres performance list, too.
> 
> 
> 
> 
> Regards,
> 
> 
> Mark

I think if PostgreSQL uses semaphore for inter-process locking,
it might be a good idea to use POSIX semaphore exits in our head
branch, the new POSIX semaphore implementation now supports
process-shared, and is more light weight than SYSV semaphore,
if there is no contention, a process need not enter kernel to
acquire/release a lock. Note that I have just fixed a bug in head
branch. However RELENG_8 does not support process-shared semaphore
yet.

Regards,
David Xu