Re: Proposal: Log inability to lock pages during vacuum - Mailing list pgsql-hackers

On 2014-12-18 16:41:04 -0300, Alvaro Herrera wrote:
> +            if (scan_all)
> +                appendStringInfo(&buf, _("waited for %d buffer pins\n"),
> +                                 vacrelstats->pinned_pages);
> +            else
> +                appendStringInfo(&buf,
> +                                 _("skipped %d pages due to buffer pins\n"),
> +                                 vacrelstats->pinned_pages);

Unless I miss something this is, as mentioned before, not
correct. scan_all doesn't imply at all that we waited for buffer
pins. We only do so if lazy_check_needs_freeze(buf). Which usually won't
be true for a *significant* number of pages.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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