Re: Updated FSM display for VACUUM VERBOSE

Bruce Momjian wrote:
> pgman wrote:
> > INFO: free space map: 49 relations with free space, maximum of 1000 relations trackable
> > INFO: 17266 pages stored, 18000 pages used (with overhead)
> > INFO: 18768 pages required to store all freespace, maximum of 18000 pages allocatable (171 kB)
> > NOTICE: the number of page slots needed (18768) exceeds max_fsm_pages (18000)
> > HINT: Consider increasing the configuration parameter "max_fsm_relations"
> > to a value over 18768.
> >
> > I find this output cleaner and easier to understand. The "pages used"
> > value will match either the "required" or "maximum" value on the line
> > below.
>
> The "pages used" sentence above is wrong, and it seems the computation
> is wrong too. I just connected to another database, created, inserted,
> and deleted rows from a table and see:
>
> INFO: free space map: 50 relations with free space, maximum of 1000
> relations trackable
> INFO: 17266 pages stored, 18016 pages used (with overhead)
> INFO: 18784 pages required to store all freespace, maximum of 18000
> pages allocatable (171 kB)
> NOTICE: the number of page slots needed (18784) exceeds max_fsm_pages
> (18000)
> HINT: Consider increasing the configuration parameter "max_fsm_relations"
> to a value over 18784.
>
> The 'pages used' is greater than 18000, which isn't possible. Seems I
> have more work to do.

OK, I have simplified the patch. It doesn't use any new computations
but just displays them differently. The output is now:

INFO: free space map contains information about:
INFO: 49 relations, limit 1000 relations
INFO: 35 pages with free space, 784 pages (with overhead)
INFO: 784 pages required to track all freespace, limit 18000 pages (171 kB)

I have committed this patch to HEAD.

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Bruce Momjian | http://candle.pha.pa.us
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