Re: Performance features the 4th - Mailing list pgsql-hackers

From Jan Wieck
Subject Re: Performance features the 4th
Date
Msg-id 3FA95966.3040100@Yahoo.com
Whole thread Raw
In response to Re: Performance features the 4th  (Manfred Spraul <manfred@colorfullife.com>)
Responses Re: Performance features the 4th  (Andrew Dunstan <andrew@dunslane.net>)
Re: Performance features the 4th  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Manfred Spraul wrote:

> Jan Wieck wrote:
> 
>>
>> _Vacuum page delay_:
>>
>> Tom Lane's napping during vacuums with another tuning option. I 
>> replaced the usleep() call with a PG_DELAY(msec) macro in miscadmin.h, 
>> which does use select(2) instead. That should address the possible 
>> portability problems.
> 
> What about skipping the delay if there are no outstanding disk 
> operations? Then vacuum would get the full disk bandwidth if the system 
> is idle.

All we could do is to monitor our own recent activity. I doubt that 
anything else would be portable. And on a dedicated DB server that is 
very close to the truth anyway.

How portable is getrusage()? Could the postmaster issue that frequently 
for RUSAGE_CHILDREN and leave the result somewhere in the shared memory 
for whoever is concerned?


Jan

-- 
#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#================================================== JanWieck@Yahoo.com #



pgsql-hackers by date:

Previous
From: Neil Conway
Date:
Subject: Re: Performance features the 4th
Next
From: Jan Wieck
Date:
Subject: Re: Performance features the 4th