Subject: Re: very slow performance on filesystem meta-data in 1.6 -current
To: Jason R Thorpe <thorpej@wasabisystems.com>
From: =?ISO-8859-1?Q?Erik_=C4ngg=E5rd?= <erik.anggard@packetfront.com>
List: tech-kern
Date: 07/16/2002 02:07:46
Thanks for the tip, I'll compile a kernel with the power svaving stuff turned
off when I get to work tomorrow and see if that makes any difference. As for the
for the DOZE vs. NAP thing, if I understand the MPC7450 User's Manual correctly,
it is not possible for software to put the CPU in DOZE mode on a 7450 (as it is
on a 7410). I guess that's why the netbsd code uses NAP for 7450 instead.
/Erik

Quoting Jason R Thorpe <thorpej@wasabisystems.com>:

> On Mon, Jul 15, 2002 at 10:58:29PM +0200, Erik Änggård wrote:
> 
>  > local disk                   0.7s           19s
>  > local disk w soft updates    n/a            0.3s
>  > nfs mounted directory        1s             29s
> 
> Matt Thomas noticed a problem like this on a new Xserve ... he
> determined
> that the CPU power saving stuff was absolutely killing interrupt
> latency.
> 
> This might also be the case on your "newmac".  (I'll note that the
> "oldmac"
> uses DOZE mode while the "newmac" uses NAP mode.)
> 
> -- 
>         -- Jason R. Thorpe <thorpej@wasabisystems.com>
>