Re: Unresponiveness of 2.4.16

[GOTO Masanori]

At Mon, 26 Nov 2001 14:44:19 -0800,
Lincoln Dale <[e-mail]> wrote:
> At 10:17 PM 26/11/2001 +0000, Alan Cox wrote:
> > > 2.4.16 becomes very unresponsive for 30 seconds or so at a time during
> > > large unarchiving of tarballs, like tar -zxf mozilla-src.tar.gz. The
> > > file is about 36mb. I run top in one window, run free repeatedly in
> >
> >This seems to be one of the small as yet unresolved problems with the newer
> >VM code in 2.4.16. I've not managed to prove its the VM or the differing
> >I/O scheduling rules however.
> 
> it is I/O scheduling.
> 
> i have a system with a large amount of RAM.
> it has both 15K RPM SCSI disks (off a symbios controller) and some bog-slow 
> IDE/ATA disks which the system decides to use PIO for rather than DMA.  (i 
> don't use them for anything other than bootup so don't really care about it 
> deciding to use PIO..).
> 
> a copy to/from the 15K RPM SCSI disks doesn't show any performance problems.
> a copy to/from the PIO-based IDE disks has the same effect -- 20/30 seconds 
> of no interactiveness -- even a "vmstat 1" *stops* for 20-30 seconds while 
> 200+MB of buffer-cache data gets written out to disk.

I guess this problem repeatly posted...
Is it related with IDE chip or chipset code?
I use Athlon on KT133A plus 2 IDE disks, and I'm also experiencing
such problem with only 1 disk. But I don't know it's PIO-based or not.

-- gotom