TSO

[Jack Vogel]

Drivers have to work with whatever the requirements/limitations of the
hardware,
if you have a 5 lb sack you shouldn't be surprised if some drops when you
shove
6 lbs at it :)

Why not have this limit in the interface so the stack can avoid exceeding
it?

Jack




On Wed, Feb 26, 2014 at 10:07 AM, John-Mark Gurney <jmg at funkthat.com> wrote:

> Sami Halabi wrote this message on Wed, Feb 26, 2014 at 19:37 +0200:
> > I'm reading (almost) all mailing emails in mailig list...
> >
> > Almost every / many problem in network performancr / packets loss ended
> up
> > suggesting disabling TSO.
> >
> > I wonder why.. Is it a bug in the implementation? Or bybdesign?
> > What are the usecases that TSO is needed? Myabe  it should be disabled bt
> > default?
>
> It looks like most of the problems are in drivers that don't handle
> packets with a large number of segments properly...  The problem is
> that some drivers limit to how segments a packet can be broken into, and
> then if they receive such a packet, instead of doing their darnest to
> deliver it, they drop it...
>
> There are some patches that help address the issue...
>
> Drivers should complain more loudly when a packet gets dropped by the
> driver, since it is likely that the OS may retry the same packet,
> just to have it fail, though sometimes it'll try a different set, and
> it might go through, so all the user may notice is a slight lag if
> they notice anything at all...
>
> --
>   John-Mark Gurney                              Voice: +1 415 225 5579
>
>      "All that I will do, has been done, All that I have, has not."
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