Re: [WIP] shared row locks

On Mon, Mar 28, 2005 at 11:18:05PM -0500, Tom Lane wrote:
> Alvaro Herrera <alvherre@dcc.uchile.cl> writes:
> > 1. To examine a tuple one must first call LockTuple, which grabs a pin
> > and lock in the buffer.  The buffer lock is released right away, but the
> > pin is kept.
>
> Surely you don't mean that *every* access to a tuple now has to go
> through the lock manager :-(.

Hmm.  Only updates (delete/select for update) of the tuples, not a
vanilla select.  Is that what you mean?  I realize I left out the fact
that the old rule still applies when dealing with standard select.

Oh, that's a big hole in the reasoning.  The buffer has to be locked
still in 3 because of this.  Will fix.

>  Have you done any performance testing?

Not really.  Will do tomorrow.

--
Alvaro Herrera (<alvherre[@]dcc.uchile.cl>)
"La principal característica humana es la tontería"
(Augusto Monterroso)