Re: Debugging deadlocks

On Fri, Apr 01, 2005 at 07:41:54PM -0500, Paul Tillotson wrote:

Hi,

> I suppose there must be reasons not to do this, but have you considered 
> using the "slack" space (empty space) in an ordinary table "heap" page 
> to store share-locks on the tuples in that page?  (If not enough space 
> is available then you would still need to use the spilled-to-disk btree 
> structure.)

No, I hadn't considered it.  However this seems hard to do, because the
"slack space" does not have a start point; on each page, elements
(tuples) grow from the back to the front, while element pointers grow
in the reverse direction.  So I don't see how would this be done.

I've been discussing this with Bruce who has an idea completely
different from mine (basically to extend the current tuple locking
system instead of extending the lock manager).  I'm still unsure about
the whole thing.

-- 
Alvaro Herrera ()
"Ni aun el genio muy grande llegaría muy lejos
si tuviera que sacarlo todo de su propio interior" (Goethe)