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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: PSINet/Cogent Latency
As you probably guessed, I do... TCP is designed to not saturate links, so... If you take what should be 60 megs of traffic and put it limit it to 45, else queue for a while, or drop if queue full... The sessions will slow-start back up to a slow enough speed that wont drop. No (or very little) packet loss, but lower quality of service anyway. --Phil -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Alex Rubenstein Sent: Tuesday, July 23, 2002 12:05 AM To: [email protected] Cc: [email protected] Subject: RE: PSINet/Cogent Latency An effective way would to graph queue drops: Serial4/1/1 is up, line protocol is up Description: to PSI via 3x-xxx-xxx-xxxx Internet address is 154.13.64.22/30 Last clearing of "show interface" counters 5w4d Queueing strategy: fifo Output queue 0/40, 2275 drops; input queue 0/75, 0 drops 30 second input rate 5000 bits/sec, 6 packets/sec 30 second output rate 39911000 bits/sec, 4697 packets/sec 144472370 packets input, 2769590243 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 1 giants, 0 throttles 0 parity 5 input errors, 5 CRC, 0 frame, 0 overrun, 1 ignored, 0 abort 1969955129 packets output, 430008350 bytes, 0 underruns FYI, for those of you commenting on my full PSI pipe, with a very small queue depth of only 40 packets, we've seen 0.00011548% percent drop -- 1 in every 865914 packets sent. Agreed, not 0%, but still, arguably that would never, ever be noticed by anyone. Once again, I don't condone; however, 1/10000th of a percent of packet loss is easily worth the decreased cost in traffic sent to this endpoint. Anyone disagree? (an important a seperate note is that CAR/CEF drops due to ICMP reaching over 10 mb/s would trigger the same counter) On Mon, 22 Jul 2002, [email protected] wrote: > > Is there patch or special config example available that would allow me > to use mrtg (or rather rrdtool) to measure more often and then graph > it in a way that would show standard 5-min graph but also separate > line showing those micro burst and actual peak usage? > > On Mon, 22 Jul 2002, Randy Bush wrote: > > > > > > 40mb/s isn't "loaded" for a DS3? > > > > if you are measuring 40mb at five min intervals, micro peaks are > > pegged out causing serious packet loss. > > > > randy > > > -- Alex Rubenstein, AR97, K2AHR, [email protected], latency, Al Reuben -- -- Net Access Corporation, 800-NET-ME-36, http://www.nac.net --
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