Re: pg_upgrade: Pass -j down to vacuumdb

Hi,

On 1/29/19 12:08 AM, Michael Paquier wrote:
> On Tue, Jan 29, 2019 at 12:35:30AM +0000, Jamison, Kirk wrote:
>> I just checked the patch.
>> As per advice, you removed the versioning and specified --jobs.
>> The patch still applies, builds and passed the tests successfully.
>
> I would document the optional VACUUM_OPTS on the page of pg_upgrade.
> If Peter thinks it is fine to not do so, that's fine for me as well.
>

I added most of the documentation back, as requested by Kirk.

> It seems to me that the latest patch sent is incorrect for multiple
> reasons:
> 1) You still enforce -j to use the number of jobs that the caller of
> pg_upgrade provides, and we agreed that both things are separate
> concepts upthread, no? What has been suggested by Alvaro is to add a
> comment so as one can use VACUUM_OPTS with -j optionally, instead of
> suggesting a full-fledged vacuumdb command which depends on what
> pg_upgrade uses. So there is no actual need for the if/else
> complication business.

I think it is ok for the echo command to highlight to the user that
running --analyze-only using the same amount of jobs will give a faster
result.

> 2) Perhaps we need to worry about the second vacuumdb --all command,
> which may want custom options, which are not necessarily the same as
> the options of the first command? I don't think we need to care as it
> applies only to an upgraded cluster using something older 8.4, just
> wondering..

I think that --all --analyze-in-stages is what most people want. And
with the $VACUUMDB_OPTS variable people have an option to put in more,
such as -j X.

Best regards,
Jesper