Socket send-buffer auto-sizing

I'm continuing to test one-way tcp streams in 3.5.0-rc1 on a wifi network.

When I do not specify a send buffer size, and thus use the kernel defaults, max speed is about 77Mbps.

When I specify 512KB send-buffer, I get speeds up to 185Mbps.

When set to 1MB, I get about 198Mbps (and setting higher does not increase the throughput after this).

This is without any 'delack' patches applied.

My question is: Should the kernel auto-tuner work better?

I seem to recall a comments from some years ago that applications should no longer attempt to tune send/recv buffers because the kernel was smart enough to get it at least mostly right.

Thanks,
Ben

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com