Re: Modifying TOAST_TUPLE_THRESHOLD and TOAST_TUPLE_TARGET?

On Thu, Jun 11, 2009 at 4:24 PM, Kevin
Grittner<Kevin.Grittner@wicourts.gov> wrote:
>
> I thought that's the behavior of EXTENDED.  The fine manual says "MAIN
> allows compression but not out-of-line storage. (Actually, out-of-line
> storage will still be performed for such columns, but only as a last
> resort when there is no other way to make the row small enough.)"
>
> If that doesn't mean that it will only use out-of-line storage when
> the row doesn't fit in the page, then the manual could use a fix.

I agree that "small enough" could be more precise. As it happens
tuptoaster.c only has one definition of "small enough" which is
whether the record is smaller than TOAST_TUPLE_THRESHOLD.

I wonder actually if this case shouldn't use the block size, not the
target size. That seems like it would be a lot more useful.

--
Gregory Stark
http://mit.edu/~gsstark/resume.pdf