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

Re: [PERFORM] Help with tuning this query (with explain analyze finally)

From: "Magnus Hagander" <mha(at)sollentuna(dot)net>
To: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Ken Egervari" <ken(at)upfactor(dot)com>,<pgsql-performance(at)postgresql(dot)org>,<pgsql-hackers-win32(at)postgresql(dot)org>
Subject: Re: [PERFORM] Help with tuning this query (with explain analyze finally)
Date: 2005-03-07 14:36:42
Message-ID: 6BCB9D8A16AC4241919521715F4D8BCE476A60@algol.sollentuna.se (view raw or flat)
Thread:
Lists: pgsql-hackers-win32pgsql-performance
> > Do we need actual high precision time, or do we just need 
> to be able 
> > to get high precision differences? Getting the differences 
> is fairly 
> > easy, but if you need to "sync up" any drif then it becomes 
> a bit more 
> > difficult.
> 
> You're right, we only care about differences not absolute 
> time.  If there's something like a microseconds-since-bootup 
> counter, it would be fine.

There is. I beleive QueryPerformanceCounter has sub-mirosecond
resolution.

Can we just replace gettimeofday() with a version that's basically:
if (never_run_before)
   GetSystemTime() and get current timer for baseline.
now = baseline + current timer - baseline timer;
return now;


Or do we need to make changes at the points where the function is
actually called?


//Magnus

Responses

pgsql-performance by date

Next:From: Tom LaneDate: 2005-03-07 14:45:37
Subject: Re: [PERFORM] Help with tuning this query (with explain analyze finally)
Previous:From: Tom LaneDate: 2005-03-07 14:11:05
Subject: Re: [PERFORM] Help with tuning this query (with explain analyze finally)

pgsql-hackers-win32 by date

Next:From: Tom LaneDate: 2005-03-07 14:45:37
Subject: Re: [PERFORM] Help with tuning this query (with explain analyze finally)
Previous:From: Tom LaneDate: 2005-03-07 14:11:05
Subject: Re: [PERFORM] Help with tuning this query (with explain analyze finally)

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