jdarcy@seqp4.ORG (Jeffrey d'Arcy) (03/25/91)
torek@elf.ee.lbl.gov (Chris Torek) writes: >At the time the NSS routers peaked out at not much >over 300 packets per second, and certainly under 1000 packets per second. > [...] >There was also mention of someone `getting the packet >forwarding cost down to about 14,000 instructions' (these being on IBM >ROMPs)---apparently this was an improvement that was not yet in place. Ugh! I knew the routers were inefficient, but this level of nonperformance defies comprehension. Sounds like time for an upgrade; they could probably get better performance with a Mac, and they could draw pretty pictures with it too.
torek@elf.ee.lbl.gov (Chris Torek) (03/27/91)
>In article <11378@dog.ee.lbl.gov> I wrote: >>At the time the NSS routers peaked out at ... under 1000 packets per second. In article <706@seqp4.UUCP> jdarcy@seqp4.ORG (Jeffrey d'Arcy) writes: >Ugh! I knew the routers were inefficient, but this level of nonperformance >defies comprehension. Indeed. One hopes it has been improved since then. (In fact, I think I remember something that implies it has: the MCI boxes that split each T1 into three virtual cables, and---for performance---often bypassed the NSS routers anyway [and note that the MCI boxes had no trouble keeping up with T1 links], have been removed.) I was just looking at a previous Usenix conference proceedings (Winter 1990), in which a paper on NSFnet traffic characterization noted that a 1-millisecond time stamp was sufficient because the machines could not receive more than one packet, regardless of length, in that time. This also implies `under 1000 packets per second', so perhaps my memory was not far off.... In any case, there is no real excuse not to be able to route at Ethernet speeds or better, these days. Given the fact that > 1Gbps optical links will be in place any day now, routing performance is going to be critical. I am on the `IRC side' (if there can be said to be such a thing) in this matter; I just refuse to pretend that current systems make IRC (or indeed any small-packet system) as cheap as it should be. -- In-Real-Life: Chris Torek, Lawrence Berkeley Lab CSE/EE (+1 415 486 5427) Berkeley, CA Domain: torek@ee.lbl.gov