Re: [ADMIN] restoring from dump

Hi Alvaro,

> Maybe initdb was executed?

Yes.  I installed 8.3.3 afresh and as a part of
such initdb was executed.  I have saved (renamed)
the previous distribution (8.3.0) and there are
many files in pg_clog directory there.  The oldest
one is named 00, and consecutively named in hex
2 digit name as 01, 02, .. , 09, 0A, 0B, .. , 84.
Then it skipped to 88 (no 85, 86, 87).  The size
of each file is 262144 bytes, with exception of
88, which is 163840.

I just looked at the one in new (8.3.3) directory:
  -bash-3.00$ date
  Tue Aug 26 08:40:35 PDT 2008
  -bash-3.00$ pwd
  /usr/local/pgsql/data/pg_clog
  -bash-3.00$ ll
  total 24
  -rw-------  1 postgres postgres 24576 Aug 26 02:33 0000

As I compare the size with what's in last night's email,
there is no difference in size.  The timestamp is in the
middle of night.

Fascinating...

Regards,

Tena Sakai
tsakai@gallo.ucsf.edu


-----Original Message-----
From: Alvaro Herrera [mailto:alvherre@commandprompt.com]
Sent: Tue 8/26/2008 7:29 AM
To: Tena Sakai
Cc: Marcelo Martins; jeff@frostconsultingllc.com; pgsql-admin@postgresql.org
Subject: Re: [ADMIN] restoring from dump

Tena Sakai wrote:
> Hi Alvaro,
>
> I just looked in pg_clog directory and there is
> only one file:
>   -rw-------  1 postgres postgres 24576 Aug 25 20:18 0000
> I saw the same file about 10:30 am and I believe
> it was roughly the same size.  This is a brand new
> installation of 8.3.3.

Maybe initdb was executed?  That would cause the files to disappear.
Of course, so would the data; it would have to be restored from a
backup.

Note that these files use only 2 bits per transaction, so in 24756 bytes
you have enough room to cover 99024 transactions.  Furthermore, they
always grow in 8192-byte increments.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.