Updating our TCP and socket sysctl values...

Gordon Tetlow gordon at tetlows.org
Sun Mar 20 01:00:20 UTC 2011

On Sat, Mar 19, 2011 at 4:13 PM, Navdeep Parhar <nparhar at gmail.com> wrote:
> 256KB seems adequate for 10G (as long as the consumer can keep
> draining the socket rcv buffer fast enough).  If you consider 2 x
> bandwidth delay product to be a reasonable socket buffer size then
> 256K allows for 10G networks with ~100ms delays.  Normally the delay
> is _way_ less than this for 10G and even 256K may be an overkill (but
> this is ok, the kernel has tcp_do_autorcvbuf on by default)

The BDP for a 10Gbps link with 100ms delay is about 120MB.

Here's a decent calculator for figuring it out:


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