On Sat, Jul 14, 2012 at 10:20:41AM +0200, Eric Dumazet wrote: > > On Tue, Jul 3, 2012 at 8:02 AM, Willy Tarreau <[email protected]> wrote: > > > > > > In fact it has been true zero copy in 2.6.25 until we faced a large > > > amount of data corruption and the zero copy was disabled in 2.6.25.X. > > > Since then it remained that way until you brought your patches to > > > re-instantiate it. > > Might be, or not (could be a NIC bug)
I may be wrong but what I recall from this bug was an issue when forwarding TCP between two NICs, related to linear vs non-linear data (I have memories of something around data not yet ACKed being replaced before being retransmitted but I may be wrong). Anyway, the way it was fixed consisted in simply disabling the zero-copy code path. So this should be something different from what Johannes reports. Maybe a regression since then though. > Please Johannes could you try latest kernel tree ? It would be useful, especially given the amount of changes you performed in this area in latest version, it could be very possible that this new bug got fixed as a side effect ! Regards, Willy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
