| From: | Kenneth Marshall <ktm(at)it(dot)is(dot)rice(dot)edu> |
|---|---|
| To: | Simon Riggs <simon(at)2ndquadrant(dot)com> |
| Cc: | Bruce Momjian <bruce(at)momjian(dot)us>, Gregory Stark <stark(at)enterprisedb(dot)com>, Heikki Linnakangas <heikki(at)enterprisedb(dot)com>, Russell Smith <mr-russ(at)pws(dot)com(dot)au>, Darcy Buskermolen <darcyb(at)commandprompt(dot)com>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>, "Matthew T(dot) O'Connor" <matthew(at)zeut(dot)net>, Pavan Deolasee <pavan(at)enterprisedb(dot)com>, Christopher Browne <cbbrowne(at)acm(dot)org>, pgsql-general(at)postgresql(dot)org, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: [HACKERS] Autovacuum Improvements |
| Date: | 2007-01-22 19:00:34 |
| Message-ID: | 20070122190034.GC7746@it.is.rice.edu |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general pgsql-hackers |
On Mon, Jan 22, 2007 at 06:42:09PM +0000, Simon Riggs wrote:
> On Mon, 2007-01-22 at 13:27 -0500, Bruce Momjian wrote:
> > Yep, agreed on the random I/O issue. The larger question is if you have
> > a huge table, do you care to reclaim 3% of the table size, rather than
> > just vacuum it when it gets to 10% dirty? I realize the vacuum is going
> > to take a lot of time, but vacuuming to relaim 3% three times seems like
> > it is going to be more expensive than just vacuuming the 10% once. And
> > vacuuming to reclaim 1% ten times seems even more expensive. The
> > partial vacuum idea is starting to look like a loser to me again.
>
> Hold that thought! Read Heikki's Piggyback VACUUM idea on new thread...
>
> --
> Simon Riggs
> EnterpriseDB http://www.enterprisedb.com
>
There may be other functions that could leverage a similar sort of
infrastructure. For example, a long DB mining query could be registered
with the system. Then as the pieces of the table/database are brought in
to shared memory during the normal daily DB activity they can be acquired
without forcing the DB to run a very I/O expensive query when waiting a
bit for the results would be acceptable. As long as we are thinking
piggyback.
Ken
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Alvaro Herrera | 2007-01-22 19:07:42 | Re: [HACKERS] Autovacuum Improvements |
| Previous Message | Terry Lee Tucker | 2007-01-22 18:54:32 | Re: printf-like format strings |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Merlin Moncure | 2007-01-22 19:06:23 | Re: savepoint improvements |
| Previous Message | Bruce Momjian | 2007-01-22 18:52:11 | Re: [HACKERS] Win32 WEXITSTATUS too |