Re: Performance monitor signal handler

> At 13:34 12/03/01 -0800, Alfred Perlstein wrote:
> >Is it possible
> >to have a spinlock over it so that an external utility can take a snapshot
> >of it with the spinlock held?
>
> I'd suggest that locking the stats area might be a bad idea; there is only
> one writer for each backend-specific chunk, and it won't matter a hell of a
> lot if a reader gets inconsistent views (since I assume they will be
> re-reading every second or so). All the stats area should contain would be
> a bunch of counters with timestamps, I think, and the cost up writing to it
> should be kept to an absolute minimum.
>
>
> >
> >just some ideas..
> >
>
> Unfortunatley, based on prior discussions, Bruce seems quite opposed to a
> shared memory solution.

No, I like the shared memory idea. Such an idea will have to wait for
7.2, and second, there are limits to how much shared memory I can use.

Eventually, I think shared memory will be the way to go.

--
Bruce Momjian | http://candle.pha.pa.us
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