Skip site navigation (1) Skip section navigation (2)

Re: testing HS/SR - 1 vs 2 performance

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Simon Riggs <simon(at)2ndQuadrant(dot)com>
Cc: Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>, Erik Rijkers <er(at)xs4all(dot)nl>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: testing HS/SR - 1 vs 2 performance
Date: 2010-04-17 22:52:26
Message-ID: 9502.1271544746@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-hackers
Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> What I'm not clear on is why you've used a spinlock everywhere when only
> weak-memory thang CPUs are a problem. Why not have a weak-memory-protect
> macro that does does nada when the hardware already protects us? (i.e. a
> spinlock only for the hardware that needs it).

Well, we could certainly consider that, if we had enough places where
there was a demonstrable benefit from it.  I couldn't measure any real
slowdown from adding a spinlock in that sinval code, so I didn't propose
doing so at the time --- and I'm pretty dubious that this code is
sufficiently performance-critical to justify the work, either.

			regards, tom lane

In response to

Responses

pgsql-hackers by date

Next:From: Robert HaasDate: 2010-04-17 22:52:35
Subject: Re: master in standby mode croaks
Previous:From: Simon RiggsDate: 2010-04-17 22:46:06
Subject: Re: testing HS/SR - 1 vs 2 performance

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group