Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac,att!ucbvax!dog.ee.lbl.gov!me10.lbl.gov!milburn
From: milburn@me10.lbl.gov (John Milburn)
Newsgroups: comp.unix.internals
Subject: Re: NFS vs communications meduim (was slashes, then NFS devices)
Message-ID: <11074@dog.ee.lbl.gov>
Date: 19 Mar 91 00:19:19 GMT
References: <11061@dog.ee.lbl.gov>
Reply-To: JEMilburn@lbl.gov (John Milburn)
Organization: Lawrence Berkeley Laboratory, Berkeley
Lines: 26
X-Local-Date: Mon, 18 Mar 91 16:19:20 PST

In the referenced article torek@elf.ee.lbl.gov (Chris Torek) writes:

>Van Jacobson regulary gets around 1 MB/s (8 Mb/s) on Sun-3 (68020) boxes.
>4.3BSD-reno (a much less carefully tuned system than Van's) running on a VAX
>8250 with a DEUNA, talking to an Encore Multimax running UMax 4.3, receives
>data inside FTP at 130 kb/s or just a bit over 1 Mb/s.

>(I used `get /vmunix /dev/null' to get this number.  Note that this depends
>on the rate at which the remote machine can generate data for you.)

There are commercial implementations using Van's alogrithms.  Using an
hp9000s400 (HP/UX 7.03) connected to a locally connected sun4 (SunOS
4.1), and using the same method, "get /vmunix /dev/null", I get a
binary transfer rate of 501 Kbyte/sec or .5 MByte/s.  The hp is using
header prediction, dynamic window sizing, and Phil Karn's clamped
retransmission algorithm.

If I go to another sun4 on the other side of a cisco router, a Dec LanBridge,
and two FDDI <-> ether bridges, the rate drops to 240 Kbyte/s.


-jem
--
John Milburn             milburn@me10.lbl.gov     (415) 486-6969
"Inconceivable!"
"You use that word a lot.  I don't think it means what you think it does."