On Fri, 1 Feb 2008 15:34:21 +0100
Andi Kleen [off-list ref] wrote:

quoted

The TSO defer logic is based on your congestion window and current
window size.  So the actual frame sizes hitting your NIC attached to
your DSL probably aren't anywhere near 64KB, but probably more in line
with whatever your window size is for DSL.

DSL windows can be quite large because a lot of DSL lines have a quite
long latency due to error correction. And with ADSL2 we have upto 16Mbit
now.

quoted

I think we're having more of a disagreement of what is considered the
"normal case" user.  If you are on a slow link, such as a DSL/cable
line, your TCP window/congestion window aren't going to be big enough to
generate large TSO's, so what is the issue?  But disabling TSO, say on a

64k TSOs are likely even with DSL. Anyways even with smaller TSOs the
change still makes sense because each increase makes packet scheduling
less smooth.

-Andi

I wish there was a per-device setting for the max-size of TSO burst.


-- 
Stephen Hemminger [off-list ref]