Re: 2.6.31-rc9 kernel BUG and mvsas

[Andre Tomt <andre@tomt.net>]

Jeff Garzik wrote:
> On 09/09/2009 12:30 PM, Thomas Fjellstrom wrote:
>> No errors on that disk. Other than the one above, and its more of a 
>> warning.
>> However, I just rebooted to add some extra drives, thinking everything 
>> was
>> working a little better now that I've updated to 2.6.31-rc9, I'm 
>> treated to
>> the following two messages right after boot (and a system lockup to 
>> boot):

Jeff & Co,

Just chiming in with a "me too" comment.

Identical issues with the AOC-SASLP-MV8 card with 8 Seagate Barracuda 
7200.11 1.5TB drives using the mvsas driver. Creating a md raid array 
seems to trigger it nearly instantly, however other loads do not trigger 
it as fast (if at all, only tested briefly with paralell dd).

Not sure if its related in any way, but I also noticed that with 
parallell dd read on all ports, the card/driver tops out at 600MB/s even 
though the card is in a northbridge connected slot running in x4 mode. 
Only the first 4-5 ports run at nearly full speed, while the rest barely 
gets to read any data at all. To illustrate, it looks sort of like this 
in iostat -m:
sda 122
sdb 122
sbc 120
sdd 121
sde 100
sdf 10
sdg 5
sdh 5

Starting to think this driver has some issues with concurrency.. The 
other controllers have no issues saturating all their ports, even if 
they are on a south bridge connected slot.

Same disks/setup works just fine on AHCI and sata_mv controllers on the 
same computer, easily pushes 8-900MB/s with md software raid5/6 (Yipes!)