Re: [HACKERS] fsync method checking

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Mark Kirkwood <markir(at)paradise(dot)net(dot)nz>, pgsql-performance(at)postgresql(dot)org, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: [HACKERS] fsync method checking
Date: 2004-03-19 04:08:31
Message-ID: 200403190408.i2J48VO12436@candle.pha.pa.us
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Tom Lane wrote:
> > It really just shows whether the fsync fater the close has similar
> > timing to the one before the close. That was the best way I could think
> > to test it.
>
> Sure, but where's the "separate process" part? What this seems to test
> is whether a single process can sync its own writes through a different
> file descriptor; which is interesting but by no means the only thing we
> need to be sure of if we want to make the bgwriter handle syncing.

I am not sure how to easily test if a separate process can do the same.
I am sure it can be done, but for me it was enough to see that it works
in a single process. Unix isn't very process-centered for I/O, so I
don't think it would make much of a difference. Now, Win32, that might
be an issue.

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Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
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