> On 25 Aug 2015, at 22:47 , Chris Stankevitz <ch...@stankevitz.com> wrote: > > Hi, > > # cat /dev/urandom | ssh root@host 'cat > /dev/null' > > I use the above ssh command over a high-BDP WAN link (80 ms @ 100 Mbps). > tcpdump shows I am TCP window limited to 64 KBytes (yielding 5 Mbps). iperf > with default options gets the window opened to 500 KBytes (yielding 35 Mbps). > > Both sides of the connection: FreeBSD 10.1 w/default sshd options (except I > permit root login). In particular, HPN is not disabled. > > Can anyone explain my abysmally small TCP window? > > Can anyone recommend some tools/tricks to figure out what in FreeBSD and/or > base SSH is limiting the send/recv buffer and/or TCP window?
if you have the memory, try these sysctls: kern.ipc.maxsockbuf=146800640 net.inet.tcp.recvbuf_max=67108864 net.inet.tcp.sendbuf_max=67108864 _______________________________________________ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
