Would it be difficult to vacuum as part of a dump? The reasoning behind
this is that you have to read the table to do the dump anyway, so it
would be a good time to be able to piggy-back other operations that need
to read the entire table on top. I know vacuuming of indexes complicates
this, so it's probably not as simple as just firing off a vacuum and
copy at the same time (although that idea is probably worth testing,
since it might still be a win).
When dropping a table or index, is it's space immediately released in
the FSM?
Also, would it be possible to add some means to check the status of a
running vacuum? Even with vacuum verbose, once it starts in on a large
table you have no way to know how far along it is.
Finally, if vacuum_delay is enabled, does vacuum_cost_page_miss consider
a miss as not in the database buffer, or not in the kernel buffer? I
remember discussions about trying to track IO request times to try and
determine if something came out of kernel buffers or not, but AFAIK
that's all vaporware right now...
--
Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461