ephraim@think.COM (Ephraim Vishniac) (11/09/88)
TMC just bought two Kinetics EtherPort II cards to speed up file
transfer to our Macs because ftp through the Kinetics gateway was too
slow and error-prone. (Slow: < 4K bytes/second. Error-prone: in a set
of 34 files averaging 3.5M bytes each, two had extra bytes inserted
and had to be retransmitted.) The EtherPort cards came with NCSA
Telnet 2.1e among other software.
As soon as we got a card installed, I tried some sample transfers to
check performance. The default settings (mtu = 512, maxseg = 512,
rwin = 512) gave me 4.2KB/S. Opening the window all the way (rwin =
4096) tripled that figure to 13KB/S. (This is under system software
6.0.2, without MultiFinder since it seems cripple ftp performance.)
Unfortunately, the manual isn't very informative about the maximum
values for mtu and maxseg in the absence of a Kinetics gateway.
Questions:
1. Is there an NCSA Telnet 2.2e? I looked around briefly at
zaphod.ncsa.uiuc.edu, but I only saw 2.2, not 2.2e.
2. What are the actual limits on mtu and maxseg? Can I expect
noticably improved performance if I increase them? What are
the hazards or drawbacks of larger values?
I'm also interested in any general folk wisdom about tuning ftp, since
I'm new to this.
Thanks in advance,
Ephraim Vishniac ephraim@think.com
Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214
On two occasions I have been asked, "Pray, Mr. Babbage, if you put
into the machine wrong figures, will the right answers come out?"ephraim@think.COM (Ephraim Vishniac) (11/10/88)
In article <30734@think.UUCP> ephraim@think.COM (that's me) writes: >Questions: >1. Is there an NCSA Telnet 2.2e? I looked around briefly at > zaphod.ncsa.uiuc.edu, but I only saw 2.2, not 2.2e. OK, OK, RTFM. 2.2 combines the AppleTalk and Ethernet versions, as it says in the changes list. Now I know. >2. What are the actual limits on mtu and maxseg? Can I expect > noticably improved performance if I increase them? What are > the hazards or drawbacks of larger values? >I'm also interested in any general folk wisdom about tuning ftp, since >I'm new to this. I'm getting very confused about this. I'm retrieving files from a VAX 8800 on TMC's "main net." Running ftp directly to VAX gets me 5.3KB/S. Running ftp to the gateway machine (a Sun 3/280) or to a diskless Sun 3/50 on the same subnet as the Mac gets me 13 or 14KB/S. Can anyone explain why going straight to the VAX is a disadvantage? Ephraim Vishniac ephraim@think.com Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214 On two occasions I have been asked, "Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?"
amanda@lts.UUCP (Amanda Walker) (11/10/88)
In article <30734@think.UUCP>, ephraim@think.COM (Ephraim Vishniac) writes: [Kinetics EtherPort II] > As soon as we got a card installed, I tried some sample transfers to > check performance. The default settings (mtu = 512, maxseg = 512, > rwin = 512) gave me 4.2KB/S. Opening the window all the way (rwin = > 4096) tripled that figure to 13KB/S. (This is under system software > 6.0.2, without MultiFinder since it seems cripple ftp performance.) > Unfortunately, the manual isn't very informative about the maximum > values for mtu and maxseg in the absence of a Kinetics gateway. For hosts sitting on your Ethernet, you can bump the mtu and maxseg to 1024. This won't work for going across the internet, though, since NCSA telnet can't handle fragmentation. Also, since 6.0.2 provides the WaitNextEvent trap, telnet thinks it's under MultiFinder. Setting timeslice=0 should tweak things up a little bit. Something that may be a limiting factor about the EtherPort II is that it uses the Intel Ethernet chip, which does not handle collisions or back-to-back packets very well. > 1. Is there an NCSA Telnet 2.2e? 2.2 handles both LocalTalk and Ethernet. if you put 'hardware=ether' in your config.tel, it will use your EtherPort II. -- Amanda Walker InterCon Corporation, 11732 Bowman Green Drive, Reston, VA 22090 ...!uunet!lts!amanda / lts!amanda@uunet.uu.net
falken@caen.engin.umich.edu (David R Falkenburg) (11/11/88)
In article <30734@think.UUCP>, ephraim@think.COM (Ephraim Vishniac) writes: > > 1. Is there an NCSA Telnet 2.2e? I looked around briefly at > zaphod.ncsa.uiuc.edu, but I only saw 2.2, not 2.2e. > > Thanks in advance, > > Ephraim Vishniac ephraim@think.com > Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214 > The ethernet & KIP based telnet programs were merged in the 2.2 release. The config.tel file now contains an entry to specify what kind of network interface layer you want to use: "AppleTalk" for KIP, "EtherSC" for SCSI Ethernet devices from Kinetics, "Ether" for Ethertalk boards (kinetics and Apple), and a few more things... The 2.2 Docs and sample config.tel file conatin a great dela of info on this stuff, as well as recommended settings for maxseg,mtu, etc. -dave -- Dave Falkenburg @ University of Michigan Computer Aided Engineering Network ARPA: falken@caen.engin.umich.edu UUCP: umix!caen.engin.umich.edu!falken
minshall@kinetics.UUCP (Greg Minshall) (11/12/88)
From article <720@lts.UUCP>, by amanda@lts.UUCP (Amanda Walker): > Something that may be a limiting factor about the EtherPort II is that > it uses the Intel Ethernet chip, which does not handle collisions or > back-to-back packets very well. Actually, people have seen anywhere from 1 to 3 megabits/second (application level data) using the EtherPort II card (and we get quite reasonable(*) performance using our FTP client). Greg Minshall Kinetics ...!ucbvax!unisoft!kinetics!minshall (415)947-0998 (*) "quite reasonable"? Well, say greater than 50Kbytes/second in binary mode (depending, somewhat, on your local disk/configuration). We've seen over 90Kbytes/second at times.
amanda@lts.UUCP (Amanda Walker) (11/14/88)
In article <668@kinetics.UUCP>, minshall@kinetics.UUCP (Greg Minshall) writes: > Actually, people have seen anywhere from 1 to 3 megabits/second (application > level data) using the EtherPort II card (and we get quite reasonable(*) > performance using our FTP client). > > Greg Minshall Kinetics > ...!ucbvax!unisoft!kinetics!minshall (415)947-0998 > > (*) "quite reasonable"? Well, say greater than 50Kbytes/second in binary > mode (depending, somewhat, on your local disk/configuration). We've seen > over 90Kbytes/second at times. Lest anyone misunderstand me, I like the EtherPort II. I have one in my Mac II, and so far the FTP performance that I've measured has been limited by the other end (at the moment, a 3B2/300... Ick :-(). Anything that doesn't overload the 82586 isn't a problem. However, very fast hosts can make it an unhappy camper. Ephraim Vishniac, for example, noticed that he can talk to a Sun just fine, but gets miserably slow performance when talking to a VAX 8800 (Ephraim: please correct me if I'm wrong). Somehow I doubt it's the VAX that is the bottelneck... :-). If the hosts you're talking to are not fast enough to send more than two back-to-back Ethernet packets, you should be fine. If they are though, you might want to try various boards in your machine to see how they work *on your network* before you buy a lot of them. Disclaimers: We sell TCP/IP software for the Mac. So does Kinetics. We don't sell hardware. We like and use Kinetics hardware, in fact. -- Amanda Walker InterCon Corporation, 11732 Bowman Green Drive, Reston, VA 22090 ...!uunet!lts!amanda / lts!amanda@uunet.uu.net