Re: [pgsql-hackers-win32] Help with tuning this query (with

On Mon, Mar 07, 2005 at 09:02:38PM -0500, Tom Lane wrote:
> One thought that was bothering me was that if the CPU goes idle while
> waiting for disk I/O, its clock might stop or slow down dramatically.
> If we believed such a counter for EXPLAIN, we'd severely understate
> the cost of disk I/O.
>
> I dunno if that is the case on any Windows hardware or not, but none
> of this thread is making me feel confident that we know what
> QueryPerformanceCounter does measure.

I believe the counter is actually good in such a situation -- I'm not a Win32
guru, but I believe it is by far the best timer for measuring, well,
performance of a process like this. After all, it's what it was designed to
be :-)

OBTW, I think I can name something like 15 or 20 different function calls to
measure time in the Win32 API (all of them in use); it really is a giant
mess.

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