Re: [PROPOSAL] VACUUM Progress Checker.

On Wed, Mar 16, 2016 at 6:44 AM, Rahila Syed <rahilasyed90(at)gmail(dot)com> wrote:
>>Sorta. Committed after renaming what you called heap blocks vacuumed
>>back to heap blocks scanned, adding heap blocks vacuumed, removing the
>>overall progress meter which I don't believe will be anything close to
>>accurate, fixing some stylistic stuff, arranging to update multiple
>>counters automatically where it could otherwise produce confusion,
>>moving the new view near similar ones in the file, reformatting it to
>>follow the style of the rest of the file, exposing the counter
>>#defines via a header file in case extensions want to use them, and
>>overhauling and substantially expanding the documentation
>
> We have following lines,
>
> /* report that everything is scanned and vacuumed */
> pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_SCANNED,
> blkno);
> pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_VACUUMED,
> blkno);
>
>
> which appear before final vacuum cycle happens for any remaining dead tuples
> which may span few pages if I am not mistaken.
>
> IMO, reporting final count of heap_blks_scanned is correct here, but
> reporting final heap_blks_vacuumed can happen after the final VACUUM cycle
> for more accuracy.

You are quite right. Good catch. Fixed that, and applied Vinayak's
patch too, and fixed another mistake I saw while I was at it.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company