Path: utzoo!attcan!uunet!lll-winken!lll-tis!mordor!joyce!ames!mailrus!nrl-cmf!ukma!david From: david@ms.uky.edu (David Herron -- One of the vertebrae) Newsgroups: comp.protocols.tcp-ip Subject: Re: A 'horror story' for the books Message-ID: <10231@s.ms.uky.edu> Date: 12 Sep 88 22:51:52 GMT References: <10208@s.ms.uky.edu> <22891@amdcad.AMD.COM> Reply-To: david@ms.uky.edu (David Herron -- One of the vertebrae) Organization: U of Kentucky, Mathematical Sciences Lines: 32 First, thanks to everyone who responded to my posting. The consensus was that trailers while on the surface seeming like a good thing are, in practice, somewhat 'bad' and it's not even clear if they actually help even in their native environment. Plus there are cases (Sun's especially) where they hurt performance because the idea is too Vax specific and especially too specific to the Vax memory management. In article <22891@amdcad.AMD.COM> rpw3@amdcad.UUCP (Rob Warnock) writes: >In fact, you should have been able to watch your SMTP mail on a packet >monitor and seen the entire "HELO", etc., dialog go along just fine up >to the point that the trailer-using host blasted its first full-sized >packet at the non-trailer host... whereupon the trailer'd packet would >be periodically retransmitted until the connection timed out. Well, being able to watch my SMTP mail on a packet monitor assumes the presence of a packet monitor in the first place. The closest I have is tcpdump which, that I know of, does not display the contents of the packet. (The joys of living in a poor state at a University which isn't yet fully up to speed on networking technology & hardware ....) Anyway. What I was seeing from the user level was the SMTP conversation succeeding up to the point where the program had finished sending all of the DATA section. Then it went to send the '.' and hung either in sending the '.' or waiting for the response (depending on the phase of the moon, I think). Now possibly the DATA section was being buffered as much as possible, I don't remember the code that well. Certainly it looked to me (at the time) as if the code were hanging because of a short packet rather than a long one... -- <---- David Herron -- One of the MMDF guys <---- ska: David le casse\*' {rutgers,uunet}!ukma!david, david@UKMA.BITNET <---- What does the phrase "Don't work too hard" <---- have to do with the decline of the american 'work ethic'?