Re: LWLOCK_STATS

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

To: Robert Haas <robertmhaas@gmail.com>

Cc: pgsql-hackers@postgresql.org

Date: 2012-01-07T07:58:05Z

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On 07.01.2012 00:24, Robert Haas wrote:
> It's been a while since I did any testing with LWLOCK_STATS defined,
> so I thought it might be about time to do that again and see how
> things look.  Here's how they looked back in July:
>
> http://archives.postgresql.org/pgsql-hackers/2011-07/msg01373.php

Interesting.

A couple of weeks ago I wrote a little patch that's similar to 
LWLOCK_STATS, but it prints out % of wallclock time that is spent 
acquiring, releasing, or waiting for a lock. I find that more useful 
than the counters.

Here's the patch, I hope it's useful to others. It uses timer_create() 
and timer_settime(), so it probably won't work on all platforms, and 
requires linking with -lrt.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com