Horton

Re: Interruptible sleeps (was Re: CommitFest 2009-07: Yay, Kevin! Thanks, reviewers!)

Robert Haas <robertmhaas@gmail.com>

View thread
From: Robert Haas <robertmhaas@gmail.com>
To: Greg Smith <greg@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, pgsql-hackers@postgresql.org
Date: 2010-08-27T22:13:11Z
Lists: pgsql-hackers 
On Fri, Aug 27, 2010 at 5:54 PM, Greg Smith <greg@2ndquadrant.com> wrote:
> Tom Lane wrote:
>>
>> Well, yes they are.  They cause unnecessary process wakeups and thereby
>> consume cycles even when the database is idle.  See for example a
>> longstanding complaint here:
>> https://bugzilla.redhat.com/show_bug.cgi?id=252129
>>
>> If we're going to go to the trouble of having a mechanism like this,
>> I'd like it to fix that problem so I can close out that bug.
>
> The way the background writer wakes up periodically to absorb fsync requests
> is already way too infrequent on a busy system.

Maybe instead of a fixed-duration sleep we could wake it up when it
needs to do something.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company