art@ACC.ARPA (10/17/85)
Before we reinvent another wheel, I'll try the network... On BSD 4.2 we have been using FTP (in binary mode) to obtain TCP/IP performance numbers for traffic through various network configurations. These figures can be (and have been seen to be) impacted by internal FTP overhead and especially disk I/O bandwidth. What I want is one program which opens a TCP connection and sends blocks of data (data source) and another program which accepts a TCP connection and discards the data (data sink). The internet address, block size and block count should be program arguments. Both source and sink programs should calculate and display throughput statistics. These should be as simple as possible to minimize CPU loading. If anyone has anything like this or could be used as a starting point I would appreciate a copy. "Art Berggreen"<Art@ACC.ARPA> ------
MILLS@USC-ISID.ARPA (10/18/85)
In response to the message sent 17 Oct 85 12:24:00 PDT from <art@acc.arpa> Art, I suggest you contact Ed Cain (cain@edn-unix.arpa), chairman of the Testing Task Force. He may either ping the members or point you to the Protocol Testing Laboratory at DCEC or both. Many old grizzlies, myself included have well-worn TCP testing machinery, but it is not the kind you simply drop into 4.2 and turn the key. Dave -------
clements@BBNCCQ.ARPA (Bob Clements) (10/18/85)
[Art @ ACC.ARPA asked about date source/sink programs that avoid the overhead of using the disk for the data.] Art, The original TENEX/TOPS20 FTP server, which I wrote many years ago, had a "feature" to do exactly what you are looking for: It recognized the "NUL:" device as a special case. Data sent to NUL: was discarded immediately by the FTP server, without even calling the file system to discard it. Data requested FROM the NUL: device was generated by the FTP server itself, and it sent a fixed amount, one megabyte or one megabit, I think. Sadly, I have been exiled from 36-bit land for a while, so I don't know whether that feature is still in the current server. I hope so. /Rcc