On 2000-Aug-10 15:36:01 +1000, Peter Jeremy <[EMAIL PROTECTED]> wrote:
>I just noticed a really peculiar network slowdown with -current from
>about a week ago. The machine has two NICs - an old 16-bit SMC card
>(ed0) running 10baseT and a PCI SMC card (tx0) running 100baseTX full
>duplex.
>
>When I scp (either ssh-1.2.27 or OpenSSH) to a remote machine via ed0,
>I get a throughput of ~8KB/sec. When I go via tx0, I get ~3MB/sec
>(CPU limited). If I use ftp via ed0, I get wire speed (just over
>1MB/sec).
Having done some more tests, and a bit more digging, I've found
the culprit is net.inet.tcp.newreno. When set to 1 (the default),
ssh (but not FTP) connections to hosts not on the same subnet
(as determined by in_localaddr()) have an effective window size of
1 MSS.
Unfortunately, I can't see any obvious reason why initialising
maxburst to 4 results in only a single packet on each call to
tcp_output() for ssh connections.
Peter
To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-current" in the body of the message
