Re: pg_xlog - files are guaranteed to be sequentialy named?

From: Johannes Konert <jkonert(at)t3go(dot)de>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: pg_xlog - files are guaranteed to be sequentialy named?
Date: 2007-06-13 17:05:11
Message-ID: 467023C7.3060007@t3go.de
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Johannes Konert wrote:
> But during the day I came out with an solution: I store the WAL-files
> with the time-stamp of archiving in their file-name. Thus I can order
> and delete them safely.
> Your hint was the one, that helped me to find that solution - so
> thanks for that, Greg.....and the others.
That solution has still a problem: It workes fine in case that the
WAL-naming restarts with 000000000000000000000001, because the attached
timestamp in name would still make it possible to identify the file as
being a newer one as FFFFFFFFFFFFFFFFFFFFFFFF, but there is still the
problem with shifts in time itself.
If someone corrects the servers computer-time/date to a date before
current time (e.g. set the clock two hours back), then the newer WAL
files will have an older timestamp and will be deleted by accident.

Thus now I increase the number of characters of the filename to infinite
and the last 24 characters are the WAL file name. Thus the archived
filenames ~always~ increase in naming and all backup files before the
last base backup can be safely identified not relying on computer
timestamps or with the risk of a restart in naming by postgresql.
I hope this solutions only border is the 255 character restriction of
file-name length....but if that one will be reached in future times I am
sure longer names are possible :)

Regards Johannes

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Greg Smith 2007-06-13 17:54:11 Re: pg_xlog - files are guaranteed to be sequentialy named?
Previous Message Johannes Konert 2007-06-13 16:42:40 Re: pg_xlog - files are guaranteed to be sequentialy named?