Обсуждение: BUG #5397: powertop reports excessive wakeups

The following bug has been logged online:

Bug reference:      5397
Logged by:          Steve White
Email address:      Stevan_White@hotmail.com
PostgreSQL version: 8.4.2
Operating system:   Ubuntu 10.5 beta
Description:        powertop reports excessive wakeups
Details:

This is a Samsung NC20.  The goal is to use this machine for occasional
testing of a database, but to keep its power consumption minimal.

Intel powertop reports the second biggest cause of wakeups (after the
network device ath) is postgres:

Top causes for wakeups
  23.6% ( 11.7)D  postgres

This is with a cleanly installed database, not being accessed at all.

Cheers!

Steve White wrote:

> This is a Samsung NC20.  The goal is to use this machine for occasional
> testing of a database, but to keep its power consumption minimal.
>
> Intel powertop reports the second biggest cause of wakeups (after the
> network device ath) is postgres:
>
> Top causes for wakeups
>   23.6% ( 11.7)D  postgres
>
> This is with a cleanly installed database, not being accessed at all.

Try raising autovacuum_naptime (or disabling autovac altogether).  There
are other background processes that wake up with some frequency; I think
bgwriter_delay and wal_writer_delay could be increased as well.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support