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To: Greg Smith <greg@2ndquadrant.com>
cc: Stephen Frost <sfrost@snowman.net>,
	Euler Taveira de Oliveira <euler@timbira.com>,
	Pgsql Hackers <pgsql-hackers@postgresql.org>
Subject: Re: [PERFORM] pgbench to the MAXINT 
In-reply-to: <4D5BCDFD.2010703@2ndquadrant.com> 
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Comments: In-reply-to Greg Smith <greg@2ndquadrant.com>
	message dated "Wed, 16 Feb 2011 08:15:41 -0500"
Date: Wed, 16 Feb 2011 10:40:31 -0500
Message-ID: <25309.1297870831@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Greg Smith <greg@2ndquadrant.com> writes:
> Given that pgbench will run with threads in some multi-worker 
> configurations, after some more portability research I think odds are 
> good we'd get nailed by 
> http://sourceware.org/bugzilla/show_bug.cgi?id=10320 : "erand48 
> implementation not thread safe but POSIX says it should be".  The AIX 
> docs have a similar warning on them, so who knows how many versions of 
> that library have the same issue.

FWIW, I think that bug report is effectively complaining that if you use
both drand48 and erand48, the former can impact the latter.  If you use
only erand48, I don't see that there's any problem.

			regards, tom lane