FERGUSON@TMASL.EXXON.COM (07/21/89)
Why is it that typical FTP data rates are only in the area of 50 kbytes/sec? I've got an ethernet link between a DN4000 and another machine, no other hosts on the wire. I figured I'd have to be getting few to no collisions, and that my throughput would be great. Wrong. I'm using thin wire...would I gaining much by going to thick? Is FTP just a crappy way to move files? Would NFS give me significantly better throughput? I know about the better transparency, but how's the performance? I see variations in data rate (on the comments made by FTP) from 30 kbytes/sec to 90 kbytes/sec, which seems kind of flaky to me. Does FTP create its own collisions? This brings up another point. I've heard lots of salespeople talking about 100 Mbit/sec Ethernet, and FDDI fiber optic 100 Mbit/sec network support coming up. When can we users expect actual products? Thanks to all, Scott Ferguson ferguson@erevax.bitnet Exxon Research & Engineering Annandale, NJ 08801 (201) 730-2339
SRFERGU@ERENJ.BITNET (Scott Ferguson) (04/10/90)
I've got two machines on their own solo Ethernet link. Using ftp, my realized data rates vary from 30-100 kbytes/sec, most of the time I see about 50 K/sec. Now, if 10 Mbits/sec ideally equals 1.25 Mbytes/sec (not counting for packet headers, error checking, etc), I'm seeing things very far from the peak throughput. Now, people are saying that on a 2-node link I should get no collisions, and see up to 50% of ideal, which would be 500 Kbytes/sec, right? I'M GETTING A TENTH OF THAT! WHY? The two machines are a DN4000 which is not burdened by multiple users or processes, and an Ardent Titan also dedicated to this process. I guess I need to consider disk write times as well for file transfers, but shouldn't I be doing a little better than 50 Kbytes/sec? I'm using thin wire ethernet (cheapernet), am I losing speed because of that? Thanks, Scott Ferguson srfergu@erenj.bitnet