Good evening, tonight while running my routine vacuum, the following came up on my screen:

---8<---------------
NOTICE:  Rel xamefiles: Uninitialized page 708135 - fixing
NOTICE:  Rel xamefiles: Uninitialized page 708136 - fixing
NOTICE:  Rel xamefiles: Uninitialized page 708137 - fixing
NOTICE:  Rel xamefiles: Uninitialized page 708138 - fixing
NOTICE:  Rel xamefiles: Uninitialized page 708599 - fixing
---8<---------------

There were a lot more than this, several hundered.

Here's the general details of the DB:
	- Approximately 30,000,000 rows
	- No triggers
	- Table consists strictly of text, integers and one key ( SERIAL )
	- PostgreSQL 7.2.3 ( yes, i'll update to 7.2.4 in the next day or so )
	- Pentium III 1.2Ghz with 1Gb RAM running RedHat 8.0 ( Not my machine! )

Here's the lead up to events:

	- Two days ago I DELETE'd approximately 7 million rows
	- I proceeded to vacuum, but it was 'terminated' by another admin approximately 12 hours later
	- I restarted the vacuum, which resulted in the following stats:

		NOTICE:  Pages 701193: Changed 8459, Empty 0; Tup 21042082: Vac 0, Keep 0, UnUsed 32056923	


	- I ran the DELETE script again which purged another 200,000 rows ( approx )
	- I proceeded to vacuum, the table in question returned the following stats:

		NOTICE:  Pages 704754: Changed 9599, Empty 0; Tup 14385034: Vac 0, Keep 207650, UnUsed 38884420.

	- Today I  dropped an index off the table, ran the DELETE again, removing 457,636 rows
	- Vacuum dumped the above NOTICES.  Final output for the table is:

		NOTICE:  Index xamefiles_k_key: Pages 187175; Tuples 14521716: Deleted 666334.
	        CPU 8.92s/14.11u sec elapsed 1306.20 sec.
	
	- The vacuum is still going along fine.

	Backups are proceeding without incident ( using pg_dump )
	DELETE's are proceeding without incident

Hope this is enough information.

Kind Regards.


-- 
Paul L Daniels    http://www.pldaniels.com
Linux/Unix systems    Internet Development
ICQ#103642862,AOL:cinflex,IRC:inflex 
A.B.N. 19 500 721 806

Thu, 13 Feb 2003 15:27:01 +1000
Paul L Daniels <pldaniels@pldaniels.com>
Version 7.2.3 Vacuum abnormality
On Thu, Feb 13, 2003 at 03:27:01PM +1000, Paul L Daniels wrote:
> Good evening, tonight while running my routine vacuum, the following came up on my screen:
> 
> ---8<---------------
> NOTICE:  Rel xamefiles: Uninitialized page 708135 - fixing
> NOTICE:  Rel xamefiles: Uninitialized page 708136 - fixing
> NOTICE:  Rel xamefiles: Uninitialized page 708137 - fixing
> NOTICE:  Rel xamefiles: Uninitialized page 708138 - fixing
> NOTICE:  Rel xamefiles: Uninitialized page 708599 - fixing
> ---8<---------------

This is a known and, it turns out, not real serious bug.  See, e.g., 

http://archives.postgresql.org/pgsql-hackers/2002-11/msg00486.php

I seem to recall Tom Lane noticing (uh, a few weeks ago, I think)
that the problem happens not just on system tables.  I think 7.2.4 is
supposed to partially fix this, but ISTR that there is something
about it which can't be fixed without forcing a catalog change (which
forces initdb, and is therefore Not Allowed for dot-releases).

A

-- 
----
Andrew Sullivan                         204-4141 Yonge Street
Liberty RMS                           Toronto, Ontario Canada
<andrew@libertyrms.info>                              M2P 2A8
                                         +1 416 646 3304 x110


Mon, 17 Feb 2003 15:45:49 -0500
Andrew Sullivan <andrew@libertyrms.info>
Re: Version 7.2.3 Vacuum abnormality
Andrew Sullivan <andrew@libertyrms.info> writes:
> On Thu, Feb 13, 2003 at 03:27:01PM +1000, Paul L Daniels wrote:
>> NOTICE:  Rel xamefiles: Uninitialized page 708135 - fixing
>> NOTICE:  Rel xamefiles: Uninitialized page 708136 - fixing
>> NOTICE:  Rel xamefiles: Uninitialized page 708137 - fixing

> This is a known and, it turns out, not real serious bug.  See, e.g., 
> http://archives.postgresql.org/pgsql-hackers/2002-11/msg00486.php
> I seem to recall Tom Lane noticing (uh, a few weeks ago, I think)
> that the problem happens not just on system tables.

The mechanism I described in the above-referenced message only occurs
for nailed-in-cache system tables.  Given Daniels' report (and one or
two others) I am suspicious that there's some path whereby rd_targblock
can fail to get reset after a vacuum for non-system tables too --- but
it hasn't been identified yet.

If what Daniels saw is due to a problem like that, then it's pretty
harmless.  If it's something else, the implications might be more dire.

			regards, tom lane

Mon, 17 Feb 2003 17:42:21 -0500
Tom Lane <tgl@sss.pgh.pa.us>
Re: Version 7.2.3 Vacuum abnormality 
On Mon, Feb 17, 2003 at 05:42:21PM -0500, Tom Lane wrote:
> Andrew Sullivan <andrew@libertyrms.info> writes:
> > On Thu, Feb 13, 2003 at 03:27:01PM +1000, Paul L Daniels wrote:
> 
> > http://archives.postgresql.org/pgsql-hackers/2002-11/msg00486.php
> 
> The mechanism I described in the above-referenced message only occurs
> for nailed-in-cache system tables.  Given Daniels' report (and one or

And for ones that have been truncated?  I found this reference:

<http://groups.google.ca/groups?hl=en&lr=&ie=UTF-8&threadm=200301251026.14193.mallah%40trade-india.com&rnum=5&prev=/groups%3Fq%3DUninitialized%2Bpage%2Bgroup:comp.databases.postgresql.*%26hl%3Den%26lr%3D%26ie%3DUTF-8%26selm%3D200301251026.14193.mallah%2540trade-india.com%26rnum%3D5>

(Sorry about the long line.  I'm still having no luck with
archives.postgresql.org).

A

-- 
----
Andrew Sullivan                         204-4141 Yonge Street
Liberty RMS                           Toronto, Ontario Canada
<andrew@libertyrms.info>                              M2P 2A8
                                         +1 416 646 3304 x110


Tue, 18 Feb 2003 17:48:18 -0500
Andrew Sullivan <andrew@libertyrms.info>
Re: Version 7.2.3 Vacuum abnormality
Andrew Sullivan <andrew@libertyrms.info> writes:
> On Mon, Feb 17, 2003 at 05:42:21PM -0500, Tom Lane wrote:
>> The mechanism I described in the above-referenced message only occurs
>> for nailed-in-cache system tables.  Given Daniels' report (and one or

> And for ones that have been truncated?  I found this reference:

> <http://groups.google.ca/groups?hl=en&lr=&ie=UTF-8&threadm=200301251026.14193.mallah%40trade-india.com&rnum=5&prev=/groups%3Fq%3DUninitialized%2Bpage%2Bgroup:comp.databases.postgresql.*%26hl%3Den%26lr%3D%26ie%3DUTF-8%26selm%3D200301251026.14193.mallah%2540trade-india.com%26rnum%3D5>

Sigh, I must be losing brain cells faster than I thought.  I completely
forgot about the TRUNCATE version of the problem.

Of course, if the complainant hasn't done TRUNCATE either, then we may
still have an issue ...

			regards, tom lane

Tue, 18 Feb 2003 19:32:31 -0500
Tom Lane <tgl@sss.pgh.pa.us>
Re: Version 7.2.3 Vacuum abnormality 