Re: PATCH: Possible solution to VM problems (take 2)

Jan Niehusmann
2000-05-18T10:59:21Z

On Thu, May 18, 2000 at 03:17:25AM -0700, Craig Kulesa wrote:
> A stubborn problem that remains is the behavior when lots of
> dirty pages pile up quickly. Doing a giant 'dd' from /dev/zero to a
> file on disk still causes gaps of unresponsiveness. Here's a short vmstat
> session on a 128 MB PIII system performing a 'dd if=/dev/zero of=dummy.dat
> bs=1024k count=256':

While 'dd if=/dev/zero of=file' can, of course, generate dirty pages at
an insane rate, I see the same unresponsiveness when doing cp -a from
one filesystem to another. (and even from a slow harddisk to a faster one).

Shouldn't the writing of dirty pages occur at least at the same rate
as reading data from the slower hard disk?

(My system: linux-2.3.99pre9-2, wait_buffers_02.patch,
truncate_inode_pages_01.patch, lvm, PII/333Mhz, 256MB, ide & scsi hard disks)

Jan