lkml.org 
[lkml]   [2002]   [Sep]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: AMD 760MPX DMA lockup
Date
On 12 September 2002 12:12, Jan Kasprzak wrote:

> my dual athlon box is unstable in some situations. I can consistently
> lock it up by running the following code:
>
> fd = open("/dev/hda3", O_RDWR);
> for (i=0; i<1024*1024; i++) {
> read(fd, buffer, 8192);
> lseek(fd, -8192, SEEK_CUR);
> write(fd, buffer, 8192);
> }

8 GB... Can you make it loop over much lesser size?

for (j=0; j<1024; j++) {
fd = open("/dev/hda3", O_RDWR);
for (i=0; i<1024; i++) {
read(fd, buffer, 8192);
lseek(fd, -8192, SEEK_CUR);
write(fd, buffer, 8192);
}
close(fd);
printf(<some stats>);
}

I assume removing read+lseek eliminates lockup?

> I tried to put the tested disk to a separate IDE controller
> (Promise PDC20269 PCI card) - then I do not get a complete lockup,
> just the drive starts to complain about the DMA timeout, and the kernel
> reesets the controller. However, DMA timeouts start to occur even on
> the primary controller.

Is it IDE related or not?
If you can test it over SCSI/NFS/ramdisk/???...

> When I switch off the DMA (hdparm -d0 /dev/hda), the problem goes away
> (however, the disk is very slow, as expected).

At which DMA/UDMA mode it starts to fail?
--
vda
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:28    [W:0.092 / U:0.304 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site