I Stratford wrote: > On Nov 12, 2007 4:01 AM, Tejun Heo <htejun@xxxxxxxxx> wrote: > >> Mikael Pettersson wrote: >>> First, a workaround for a HW erratum affecting 2nd-generation >>> chips like the SATA300 TX4 was included in kernel 2.6.24-rc2. >> ... >> Alright, if it's fixable, no problem. I just wanted to remind that >> running the link at 3Gbps isn't worth if it continues to cause problems. > > I appreciate the replies and ensuing discussion. I will test > 2.6.24-rc2 as soon as possible and let you know the results. At that > time I'll also have more runtime on the 1.5Gbps forced 2.622 and will > be able to follow-up. Would you (Tejun, Mikael) prefer that I mail > linux-ide or you directly? I checked for a linux-ide FAQ and didn't > find one.. :) Please cc all involved including linux-ide. > Mikael : >>> Secondly, Stratford's system is seriously overloaded: >>> ... >>> - problems began when two Promise 300 TX4 cards and >>> more disks were added >>> On several occasions we've traced people's problems to >>> overtaxed system components (cooling, PSU, PCI busses). > > Tejun: >> Agreed, I've seen my share of those issues. Especially, SATA links seem >> very dependent on power quality and very weird things happen when the >> power isn't good enough. Easy way to debug this is connect half of the >> drives to a separate PSU and see what happens. > > While I agree that the configuration is "seriously overloaded" (I > believe I described it as "admittedly somewhat insane" ;D) I haven't > experienced any port-resets or timeouts on my new TX4 300s, coming up > on a week of runtime with the 1.5Gbps-only 2.6.22 patched kernel. > Also, the problems did not generally extend to the two pre-existing > TX4 150s on the same PCI bus, even when the TX4 300s were having > problems. If hardware overheating/PCI overload/PSU problems were the > cause, it seems like a very lucky coincidence that stepping the TX4 > 300s to 1.5Gbps mode also resolves it. :D One thing I can tell you is power problem shows itself in highly diverse ways. Failing 3Gbps while 1.5 works fine, some subset of disks / controllers work fine while others don't. You name it. > The system's 23 drives are spread across 3 good quality power > supplies. As indicated in my initial mail, I have swapped the PSU on > the new drive with a new one, specifically a 430 watt cooler master > PSU which by my kill-a-watt gives me ~250 watts of headroom even > during spin-up. While my building power is notoriously lousy, I find a > building-power or PSU-power-quality explanation somewhat unlikely, > especially in light of the consistent performance of the two TX4 150s > and the night-and-day performance of 1.5Gbps patched 2.6.22 vice > unpatched 2.6.22 on the two TX4 300s. That said, using one or more PSUs and swapping them is the best way to rule those problems out. -- tejun - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
