Re: BufFreelistLock

Excerpts from Jeff Janes's message of vie dic 10 12:24:34 -0300 2010:
> On Fri, Dec 10, 2010 at 5:45 AM, Alvaro Herrera
> <alvherre@commandprompt.com> wrote:
> > Excerpts from Jim Nasby's message of jue dic 09 16:54:24 -0300 2010:

> >> To do that I think we'd want the bgwriter to target there being X number of buffers on the free list instead of
(orin addition to) targeting how many dirty buffers need to be written. This would mirror what operating systems do;
theystrive to keep X number of pages on the free list so that when a process needs memory it can get it quickly.
 
> >
> > Isn't it what it does if you set bgwriter_lru_maxpages to some very
> > large value?
> 
> As far as I can tell, bgwriter never adds things to the freelist.
> That is only done at start up, and when a relation or a database is
> dropped.  The clock sweep does the vast majority of the work.

AFAIU bgwriter runs the clock sweep most of the time (BgBufferSync).

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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