Re: vacuum_cost_limit doc description patch

El 11/04/18 a las 02:04, David Rowley escribió:
> On 11 April 2018 at 09:13, Martín Marqués <martin(dot)marques(at)gmail(dot)com> wrote:
>> This is a patch to add some further description, plus the upper and
>> lower limits it has.
>
> Hi,
>
> + for vacuum_cost_delay. The parameter can take a value
> between 1 and 10000.
>
> vacuum_cost_delay should be in <varname> tags.
>
> +1 to mentioning that we sleep for vacuum_cost_delay, but I just don't
> see many other GUCs with mention of their supported range.

Thanks David for having a look.

New version attached with the missing <varname> tags.

> effective_io_concurrency mentions the range it supports, but this
> happens to depend on USE_POSIX_FADVISE, which if undefined the maximum
> setting is 0, which means the docs are wrong in some cases on that.
>
> vacuum_cost_limit seems fairly fixed at 0-10000 with no compile-time
> conditions, so perhaps it's okay, providing we remember and update the
> docs if that ever changes.

I'm also adding a second patch over the config.sgml doc to fix what I
believe is a misguidance in the minimum resolution time modern systems have.

The patch just changes *many* for *some* systems which have a minimum
resolution time of 10 milliseconds.

--
Martín Marqués http://www.2ndQuadrant.com/
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