On Wed, Jun 12, 2002 at 10:03:19PM +0200, Manuel Bouyer wrote:
> On Wed, Jun 12, 2002 at 07:46:50PM +0000, Wojciech Puchar wrote:
> > cp <500MB file> otherfile
> > 
> > no delayed reactions in everything?
> 
> I didn't experience it. I tried with your settings, I also have 128M RAM.
> However I did notice a strange thing:
> for various reasons on both systems I tested,, the copy goes from/to
> a different disk than the system disk. While I do the copy,

OK, I newfs an old linux partition (which doesn't boot any more anyway).
doing a cp on the same disk as the system disk freeze X until the
cp is done.  Same result if I use dd instead of cp.
Either reading or writing a large file cause this problem (dd if=file
of=/dev/null, or dd if=/dev/zero of=file)

Has anyone idea of what is causing this ?
I suspect it could be disksort, which cause a single request to one end of
the disk be delayed to group dozen of requests on the other end of the disk.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
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