Re: Spinlocks, yet again: analysis and proposed patches

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Qingqing Zhou <zhouqq@cs.toronto.edu>
Cc: pgsql-hackers@postgresql.org
Date: 2006-06-15T02:23:01Z
Lists: pgsql-hackers
Qingqing Zhou wrote:
> 
> "Bruce Momjian" <pgman@candle.pha.pa.us> wrote
> >
> > Added to TODO list.
> >
> > > One thing we tried in February was padding out the statically defined
> > > locks with dummy lock definitions in the enum. This has the effect of
> > > ensuring that the most contested locks are very definitely in their own
> > > cache line and not shared with others.
> > > That showed a noticeable improvement in performance, probably because it
> > > costs very little to implement, even if the code would require some
> > > explanatory documentation.
> > >
> 
> Has this been done? See the LWLOCK_PADDED_SIZE macro in code.

Oh, yes, thanks.  I thought it had but I couldn't find anything in the
area of the code he propsed the patch.

-- 
  Bruce Momjian   http://candle.pha.pa.us
  EnterpriseDB    http://www.enterprisedb.com

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