Re: opportunistic tuple freezing - Mailing list pgsql-hackers

From Jeff Davis
Subject Re: opportunistic tuple freezing
Date
Msg-id 1250481700.24704.17.camel@jdavis
Whole thread Raw
In response to Re: opportunistic tuple freezing  (Greg Stark <gsstark@mit.edu>)
List pgsql-hackers
On Mon, 2009-08-17 at 04:01 +0100, Greg Stark wrote:
> If it's convenient to have a function to handle the scan then use it
> for both scans. You could have a flag that indicates it should abort
> after the first freeze. I think it would be simpler to have a return
> value indicating the oldest transaction found and then just call it
> again if that's old enough for the opportunistic threshold.

Thanks for the suggestions.

I think it will take some significant refactoring. It needs to work from
both scan_heap and lazy_scan_heap, so I would need to make a loop that
works for both of those cases. Additionally, the second scan needs to
avoid all of the side effects (like double-counting), which might mean
some ugly branching. For instance, the big switch statement is
completely unnecessary during the second scan.

I'll come up with a refactored version of the patch.

Regards,Jeff Davis



pgsql-hackers by date:

Previous
From: vanek
Date:
Subject: Re: build error
Next
From: Andrew Dunstan
Date:
Subject: Re: build error