Re: [2.6.20.21 review 12/35] TCP: Fix TCP handling of SACK in

Ilpo Järvinen wrote:

Willy Tarreau wrote:

quoted

I agree with this. The impression I got from the description of the two
patches I merged was that the problems they fix were quite annoying. But
maybe I should take that with a grain of salt.

No, it's not a grain of salt. I would say its utterly broken, out loud.
But many people are not that much into time-seq graphs (that I'm familiar
with), they are pleased when it seems to work well enough even though
from my perspective, it is simply unacceptable in worst cases (not
speaking of theoretical ones here, have seen very bad performance). Not
that it always is that bad, depends on phase of the opposite direction
what happens.

Somebody asked me when those four patches were made about this, I put
these there back then:

http://www.cs.helsinki.fi/u/ijjarvin/bidir-showcase/

They are generated from my old test archives and thus may have a bit
differences in TCP variant, which may slightly differ from mainline
here and there (my point was just to show how it breaks). Typical
people wouldn't even notice those minor differences compared with the
bidir brokeness which is very visible in all except in the fixed "ok"
case. Please judge for yourself whether I overexaggrated or not... :-)

It would probably be helpful, if you could post a specific testcase and a 
combo-patch of your fixes.


Thanks!

--
Al