Re: Higher TOAST compression.

On Fri, Jul 17, 2009 at 10:40 PM, Kevin
Grittner<Kevin.Grittner@wicourts.gov> wrote:
> Laurent Laborde <kerdezixe@gmail.com> wrote:
>
>> But... on which version are you planning to do that ?
>
> The patch, if there's consensus that it's a good idea, would be for
> 8.5.  Since it is new functionality, there wouldn't be a back-port to
> prior releases.  Of course, I wouldn't be starting to work on such a
> patch until after our current code commit phase, which ends August
> 15th.

Sure, no problem.

>> We stay on Pg 8.3 until the slony developpers find a better upgrade
>> solution.
>>
>> The proposed solution sound really good to me.
>> But, for now, if i could have a simple patch for 8.3 (eg: changing a
>> #define in the source code), i'd be very happy :)
>>
>> Is it ok to just change TOAST_TUPLES_PER_PAGE ?
>
> The thing that worries me about that is that it would tend to force
> more data to be stored out-of-line, which might *increase* your I/O;
> since the whole point of this exercise is to try to *decrease* it,
> that seems pretty iffy.  However, once we get to the end of code
> commit, I might be able to give you a little one-off patch that would
> be more aggressive about compression without affecting out-of-line
> storage.  Hard-coded, like what you're talking about, but with a
> little more finesse.

Awesome !
Yes, i understand the problem.

What about SET STORAGE MAIN then ? To prevent out-of-line storage ?
We use PLAIN on some specific column (i don't know why, it was here
before i join overblog)
And the default extended storage for all other columns.

Thank you :)

--
Laurent Laborde
Sysadmin @ http://www.over-blog.com/