> Hi,
>
> what is a single stream TCP throughput one can expect with a default
> setup and GENERIC-NODEBUG if the interface is not the limiting factor
> and it's max 5ms rtt.
>
> I am asking as I am seeing "funny things" and I am not sure if that is
> me or TCP at this point. It's IPv6 for me and the conection comes out
> of something which partially uses LinuxKPI.
>
> I seem to spend some signigicant time of tcp6_input_with_port() on a
> spinlock_exit().
>
> I thought I'd ask before I dig into that.
I believe your going to end up window size limited, which
boils down to:
Bandwidth = Windows size / RTT
Using the default freebsd window size for TCP of 2MB and your 5mS
I get 419430400 MB/sec (3.355 Gbit/s).
I have advocated to the transport group that the as shipped
default window sizes for FreeBSD are causing limitiations
on certain types of common connections now that gigabit is
common to the residence. (A 1G/bit connection on a 32mS
cable connection is limited to 65MB/s (524Mb/s)).
I suggest increasing these sizes to 16MB or 32MB which puts
FreeBSD on par with what Linux and Windows are using today.
> /bz
>
> --
> Bjoern A. Zeeb r15:7
--
Rod Grimes [email protected]
