Re: seagate disks on sil3114 - slow?

[Soeren Sonnenburg <kernel@nn7.de>]

On Fri, 2007-10-26 at 11:32 +0900, Tejun Heo wrote:
> Soeren Sonnenburg wrote:
> > On Thu, 2007-10-18 at 01:07 -0400, Jeff Garzik wrote:
> >> Soeren Sonnenburg wrote:
> >>> Dear all,
> >>>
> >>> I just now realize that all disk i.o. on my machine is quite slow
> >>> compared with the pata disks I had before. Furthermore I recognized that
> >>> I only have seagates (ST3400832AS,ST3400620AS,ST3750640AS,ST3750640AS)
> >>> connected to a sil3114 controller.
> >>>
> >>> Being on kernel 2.6.23.1 and stumbling across
> >>> http://home-tj.org/wiki/index.php/Sil_m15w I am now wondering if this
> >>> patch made it already in kernel (or when it will make it if it is not
> >>> yet in/why never).
> >> Are you sure you have a 3114?  the mod15write isn't applied to that chip.
> >> Does your dmesg say "applying Seagate errata fix (mod15write workaround)" ?
> > 
> > At least lspci / dmesg indicates I have a 3114 ... but maybe the problem
> > is something else. Is there a raw device speed, readonly benchmark to
> > check whether things are as expected?

looks like I did not fully reply to this one: yes I have a 3114 and
based on Bernds patch to enable m15w support for sil3114 I added the
first two drives to the blacklist and yes I saw the applying mod15write
workaround messages for these disks afterwards. These disks attached to
the internal promise seems to work stably now (uptime is a week now),
with the occasional error that thanks to the new EH is successfully
recovered from - good job!!

> "dd if=/dev/sdX of=/dev/null bs=1M"?  Also, does changing IO scheduler
> to deadline make any difference?

OK I knew that one... about 50-60M/s - sounds reasonable, but if I
understand the m15w problem correctly it can only be triggered on
writes...

Soeren