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Date: Wed,  5 Jan 2005 11:08:22 -0500
From: Bruce Campbell <bruce@engmail.uwaterloo.ca>
To: freebsd-questions@freebsd.org
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Subject: Re: New FreeBSD 5.3 e-mail server extremely slow - traced to
	getpwnam maybe ?
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Quoting Bruce Campbell <bruce@engmail.uwaterloo.ca>:
> > On Tue, Jan 04, 2005 at 09:27:27PM -0500, Bruce Campbell wrote:
> > 
> > > I wrote a small program:
> > > 
> > >   #include <sys/types.h>
> > >   #include <pwd.h>
> > > 
> > >   main( int argc, char *argv[] )
> > >   {
> > >   getpwuid( 13076 );
> > >   }
> > > 
> > > and ran it under truss on 5.x and it generated 178,711 lines of output.
> > > (the bulk of which is those lseek/read calls as above)

It looks like the overhaul of getpwent Apr/2003 to make it thread safe:

  http://www.freebsd.org/cgi/cvsweb.cgi/src/lib/libc/gen/getpwent.c

may be the problem.

I've tested the dbm_fetch function independently on a large
file, and it is fine.

I've opened a bug report, and plan to build a replacement 4.x
mail server, as the most deterministic path to restoring
adequate e-mail service to our users.

Can anyone suggest a workaround ?

-- 
Bruce Campbell
Engineering Computing
CPH-2374B
University of Waterloo
(519)888-4567 ext 5889

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