Re: Linux 2.6.24-rc7

["J.A. Magallón" <jamagallon@ono.com>]

On Mon, 14 Jan 2008 08:57:35 +0900, Tejun Heo <htejun@gmail.com> wrote:

> J.A. Magallón wrote:
> > I'm still pending to pysically remove the disks (or at least unplug the
> > cable...), but I have realized a cusious thing: after some errors, the
> > kernel is lowering the disk speed (UDMA/133, then 100, then 33):
> 
> That's the standard error handling behavior.  Timeouts are likely to
> indicate transmission problems so libata puts it into slower gear.
> 
> > Perhaps this gives a clue.
> > Or I just had bad luck and 2 of my 4 disks broke at the same time.
> 
> As I said, the first thing I would try is to connect the drives to a
> separate PSU and re-seating cables as you're seeing problems on two
> drives simultaneously.
> 

I finally found the bad drive (the most obvious one as I would expect,
it was recycled from an older box...).
I tried removing completely the drive from power and controller, and then
running with it powered but not connected. No single error any more on
any of the other 3 drives. I have been updating my distro, rebuilding the
rpm database, moving big files between drives, even all at the same time.
No error.

I can't believe it, but a bad drive was causing timeouts on other drive
_on other controller_, the bad one was attached to the Promise and the
good ones on the ICH5 SATA (both integrated in motherboard).
Or there is a strange interaction in my board (Asus PC-DL), or there is
a nasty bug in the kernel...

--
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free
Mandriva Linux release 2008.1 (Cooker) for i586
Linux 2.6.23-jam05 (gcc 4.2.2 20071128 (4.2.2-2mdv2008.1)) SMP PREEMPT