[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

[OT]Re: Multi-tasking

El Miércoles, 28 de Junio de 2006 13:24, cobaco (aka Bart Cornelis) escribió:
> On Wednesday 28 June 2006 12:30, André Wöbbeking wrote:
> > On Wednesday 28 June 2006 12:15, cobaco (aka Bart Cornelis) wrote:
> > > On Wednesday 28 June 2006 05:09, Matej Cepl wrote:
> > > > Hi,
> > >
> > > Is anything trying to write/read large amounts of data when this
> > > happens? if so you might want to:
> > > - check the settings for your harddisk (notably DMA)
> > > - also which filessystem are you using? reiserfs3 has problems
> > > locking up the system under high load
> >
> > I sometimes have this problem and thought that it's related to SATA. But
> > I'm using reiserfs3. Do you've more infos about its problems under high
> > load.
> YMMV, I can't remember where I read the details, but the FAQ at [1] has:
> Q: Why do things freeze on my IDE hard drive for annoying amounts of time
> A: Because when large writes are scheduled all at once, reads can starve. A
>    fix for this is evolving; the later your ReiserFS patch, the better we
>    handle this.
> (it's been over a year since I was using reiserfs, this problem made my
> laptop completely unusable for 10minutes+ when doing e.g. svn update on the
> d-i repository, i finally 'fixed' it by switching to ext3, situation might
> have improved since then)
> [1] http://www.namesys.com/faq.html
  Hello All:

  Here is something I have always liked to asks but I hadn't had the chance. 
The problem is that on my job PC, I use reiser over a LVM over a SATA disk. 
When I have some disk intensive tasks/intervals, my system turns not as 
responsive as I wish and as I think should be.

  In this situation, I have tried doing top on a konsole, and I find that the 
field "wa" in the above part of the top report, in the middle of "id" 
and "hi" raises to 80-90%. I don't know what exactly this field means, but I 
bet for cpu-wait state as it is the case in disk I/O.

  All of this guessing yields me to the conclusion that I'm sometimes wasting 
up to 90% of cpu time waiting or just doing nothing, I can't understand this. 
As I'm not sure about the SATA details (I'm used to PATA) I think I have the 
best configuration, even DMA, but this go on happening.

  On my laptop, which includes a Dell PATA disk, the supposed "wait" states 
doesn't rise bigger than 30-40%.

  What could be happening here? Is this normal?.

  Thanks for your attention. I know this is OT, but I would appreciate 
redirection to a possible source of information related to this.


     Raúl Sánchez Siles
----->Proud Debian user<-----
Linux registered user #416098

Attachment: pgpGf7CmN3GH6.pgp
Description: PGP signature

Reply to: