David Fetter <david(at)fetter(dot)org>, Dan Ports <drkp(at)csail(dot)mit(dot)edu>,
Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>,
Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>,
simon(at)2ndquadrant(dot)com, pgsql-hackers(at)postgresql(dot)org
On 02/09/2011 06:25 PM, Robert Haas wrote:
> On Wed, Feb 9, 2011 at 10:38 AM, Markus Wanner <markus(at)bluegap(dot)ch> wrote:
>> Thread based, dynamically allocatable and resizeable shared memory, as
>> most other projects and developers use, for example.
I didn't mean to say we should switch to that model. It's just *the*
other model that works (whether or not it's better in general or for
Postgres is debatable).
> Or less invasively, a small sysv shm to prevent the double-postmaster
> problem, and allocate the rest using POSIX shm.
..which allows ftruncate() to resize, right? That's the main benefit
over sysv shm which we currently use.
ISTM that addresses the resizing-of-the-overall-shared-memory question,
but doesn't that require dynamic allocation or some other kind of
book-keeping? Or do you envision all subsystems to have to
re-initialize their new (grown or shrunken) chunk of it?
Regards
Markus Wanner