Message-ID: <4E66DDE8.7080007@squeakycode.net>
Date: Tue, 06 Sep 2011 21:58:48 -0500
From: Andy Colson <andy@squeakycode.net>
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To: Pavan Deolasee <pavan.deolasee@gmail.com>
CC: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: REVIEW Single pass vacuum - take 2
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On 08/22/2011 01:22 AM, Pavan Deolasee wrote:
> Hi All,
>
> Here is a revised patch based on our earlier discussion. I implemented
> Robert's idea of tracking the vacuum generation number in the line
> pointer itself. For LP_DEAD line pointers, the lp_off/lp_len is unused
> (and always set to 0 for heap tuples). We use those 30 bits to store
> the generation number of the vacuum which would have potentially
> removed the corresponding index pointers, if the vacuum finished
> successfully. The pg_class information is used to know the status of
> the vacuum, whether it failed or succeeded. 30-bit numbers are large
> enough that we can ignore any wrap-around related issues. With this
> change, we don't need any additional header or special space in the
> page which was one of the main objection to the previous version.
>
> Other than this major change, I have added code commentary at relevant
> places and also fixed the item.h comments to reflect the change. I
> think the patch is ready for a serious review now.
>
> Thanks,
> Pavan
>

Hi Pavan, I tried to apply your patch to git master (as of just now) and it failed.  I assume that's what I should be checking out, right?

-Andy