Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To:
Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc:
Philip Warner <pjw(at)rhyme(dot)com(dot)au>, Don Baccus <dhogaza(at)pacifier(dot)com>,
pgsql-hackers(at)postgresql(dot)org, brianb-pggeneral(at)edsamail(dot)com
> It would be a bad idea to nice down a backend anyway, if the intent is
> to speed up other backends. The Unix scheduler has no idea about
> application-level locking, so you'll get priority-inversion problems:
> once the nice'd backend has acquired any sort of lock, other backends
> that may be waiting for that lock are at the mercy of the low priority
> setting. In effect, your entire database setup may be running at the
> nice'd priority relative to anything else on the system.
>
> I think Philip's idea of adding some delays into pg_dump is a reasonable
> answer. I'm just recommending a KISS approach to implementing the
> delay, in the absence of evidence that a more complex mechanism will
> actually buy anything...
I am worried about feature creep here. Does any other database
implement this? I can accept it as a config.h flag, but it seems
publishing it as a pg_dump flag is just way too complicated for users.
--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
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