Messages in this thread Patch in this message |  | | | Date | Tue, 19 Feb 2008 17:38:24 -0800 | | From | "Matt Carlson" <> | | Subject | Re: TG3 network data corruption regression 2.6.24/2.6.23.4 |
| |
On Tue, Feb 19, 2008 at 05:14:26PM -0500, Tony Battersby wrote: > Michael Chan wrote: > > On Tue, 2008-02-19 at 11:16 -0500, Tony Battersby wrote: > > > >> iSCSI > >> performance drops to 6 - 15 MB/s when the 3Com NIC is doing heavy rx > >> with light tx, > >> > > > > That's strange. The patch should only affect TX performance slightly > > since we are just turning off SG for TX. Please take an ethereal trace > > to see what's happening and compare with a good trace. > > > > > > Update: when I revert Herbert's patch in addition to applying your > patch, the iSCSI performance goes back up to 115 MB/s again in both > directions. So it looks like turning off SG for TX didn't itself cause > the performance drop, but rather that the performance drop is just > another manifestation of whatever bug is causing the data corruption. > > I do not regularly use wireshark or look at network packet dumps, so I > am not really sure what to look for. Given the above information, do > you still believe that there is value in examining the packet dump? > > Tony
Hi Tony. Can you give us the output of :
sudo lspci -vvv -xxxx -s 03:01.0' (assuming that is still the correct address of the 3Com NIC.)
Also, after some digging, I found that the 5701 can run into trouble if a 64-bit DMA read terminates early and then completes as a 32-bit transfer. The problem is reportedly very rare, but the failure mode looks like a match. Can you apply the following patch and see if it helps your performance / corruption problems?
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c index db606b6..7ad08ce 100644 --- a/drivers/net/tg3.c +++ b/drivers/net/tg3.c @@ -11409,6 +11409,8 @@ static int __devinit tg3_get_invariants(struct tg3 *tp) tp->tg3_flags |= TG3_FLAG_PCI_HIGH_SPEED; if ((pci_state_reg & PCISTATE_BUS_32BIT) != 0) tp->tg3_flags |= TG3_FLAG_PCI_32BIT; + else if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5701) + tp->grc_mode |= GRC_MODE_FORCE_PCI32BIT; /* Chip-specific fixup from Broadcom driver */ if ((tp->pci_chip_rev_id == CHIPREV_ID_5704_A0) &&
|  |