Re: [PATCHES] scan_recycle_buffers

2007-04-03 Thread Bruce Momjian
Simon Riggs wrote: > On Mon, 2007-04-02 at 19:10 -0400, Bruce Momjian wrote: > > > Where is the final version of this patch? What patches are stuck in the > > patch moderator queue? > > We already discussed the dependency that exists with this patch and you > accepted that. Oh, that was the pat

Re: [PATCHES] scan_recycle_buffers

2007-04-03 Thread Simon Riggs
On Mon, 2007-04-02 at 19:10 -0400, Bruce Momjian wrote: > Where is the final version of this patch? What patches are stuck in the > patch moderator queue? We already discussed the dependency that exists with this patch and you accepted that. -- Simon Riggs EnterpriseDB http:

Re: [PATCHES] scan_recycle_buffers

2007-04-02 Thread Bruce Momjian
Where is the final version of this patch? What patches are stuck in the patch moderator queue? --- Simon Riggs wrote: > On Sat, 2007-03-10 at 07:59 +, Simon Riggs wrote: > > On Fri, 2007-03-09 at 18:05 -0500, Tom Lane w

Re: [PATCHES] scan_recycle_buffers

2007-03-10 Thread Simon Riggs
On Sat, 2007-03-10 at 23:26 +1300, Mark Kirkwood wrote: > Simon Riggs wrote: > > New patch enclosed, implementation as you've requested. > > > > Not ready to apply yet, but good for testing. > > > > A quick test using the setup for "Buffer cache is not scan resistant" > thread: > > Firstly van

Re: [PATCHES] scan_recycle_buffers

2007-03-10 Thread Mark Kirkwood
Simon Riggs wrote: On Sat, 2007-03-10 at 07:59 +, Simon Riggs wrote: On Fri, 2007-03-09 at 18:05 -0500, Tom Lane wrote: "Simon Riggs" <[EMAIL PROTECTED]> writes: On Fri, 2007-03-09 at 16:45 -0500, Tom Lane wrote: We do that anyway; but certainly Simon's patch ought not be injecting an add

Re: [PATCHES] scan_recycle_buffers

2007-03-10 Thread Simon Riggs
On Sat, 2007-03-10 at 07:59 +, Simon Riggs wrote: > On Fri, 2007-03-09 at 18:05 -0500, Tom Lane wrote: > > "Simon Riggs" <[EMAIL PROTECTED]> writes: > > > On Fri, 2007-03-09 at 16:45 -0500, Tom Lane wrote: > > >> We do that anyway; but certainly Simon's patch ought not be injecting > > >> an ad

Re: [PATCHES] scan_recycle_buffers

2007-03-10 Thread Simon Riggs
On Fri, 2007-03-09 at 18:05 -0500, Tom Lane wrote: > "Simon Riggs" <[EMAIL PROTECTED]> writes: > > On Fri, 2007-03-09 at 16:45 -0500, Tom Lane wrote: > >> We do that anyway; but certainly Simon's patch ought not be injecting > >> an additional one. > > > It should be possible to pass that down fro

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Jeff Davis
On Fri, 2007-03-09 at 20:08 +, Heikki Linnakangas wrote: > Simon Riggs wrote: > > Patch to implement buffer cache recycling for scans, as being discussed > > on pgsql-hackers. > > A few questions come to mind: > > How does it behave with Jeff's synchronized seq scans patch? > I will test it

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Jeff Davis
On Fri, 2007-03-09 at 20:37 +, Simon Riggs wrote: > > I wonder if calling RelationGetNumberOfBlocks on every seq scan becomes > > a performance issue for tiny tables with for example just 1 page. It > > performs an lseek, which isn't free. > > Jeff's patch does this also, for similar reasons

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Tom Lane
"Simon Riggs" <[EMAIL PROTECTED]> writes: > On Fri, 2007-03-09 at 16:45 -0500, Tom Lane wrote: >> We do that anyway; but certainly Simon's patch ought not be injecting >> an additional one. > It should be possible to pass that down from the planner to the > executor, in certain cases. Huh? See H

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Simon Riggs
On Fri, 2007-03-09 at 16:45 -0500, Tom Lane wrote: > Heikki Linnakangas <[EMAIL PROTECTED]> writes: > > I wonder if calling RelationGetNumberOfBlocks on every seq scan becomes > > a performance issue for tiny tables with for example just 1 page. It > > performs an lseek, which isn't free. > > We

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Tom Lane
Heikki Linnakangas <[EMAIL PROTECTED]> writes: > I wonder if calling RelationGetNumberOfBlocks on every seq scan becomes > a performance issue for tiny tables with for example just 1 page. It > performs an lseek, which isn't free. We do that anyway; but certainly Simon's patch ought not be injec

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Simon Riggs
On Fri, 2007-03-09 at 20:08 +, Heikki Linnakangas wrote: > Simon Riggs wrote: > > Patch to implement buffer cache recycling for scans, as being discussed > > on pgsql-hackers. > > A few questions come to mind: Good questions. I don't expect this will go through easily, so we need to examine t

Re: [PATCHES] scan_recycle_buffers

2007-03-09 Thread Heikki Linnakangas
Simon Riggs wrote: Patch to implement buffer cache recycling for scans, as being discussed on pgsql-hackers. A few questions come to mind: How does it behave with Jeff's synchronized seq scans patch? I wonder if calling RelationGetNumberOfBlocks on every seq scan becomes a performance issue

[PATCHES] scan_recycle_buffers

2007-03-09 Thread Simon Riggs
Patch to implement buffer cache recycling for scans, as being discussed on pgsql-hackers. Applies cleanly to cvstip, passes make installcheck when used by default for all SeqScans. Tested with scan_recycle_buffers = 1,4,8,16 Should be regarded as WIP. Presumably there are some failure conditions