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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: PSINet/Cogent Latency
I have a small RRD project box that polls 200 interfaces and has it takes 1 minute, 5 seconds to run with 60% cpu usage (so obviously it can be streamlined if I wanted to work on it). I guess the limit in this implementation is 1000 interfaces per box in this setup -- but I see most of the CPU usage is in the forking of snmpget over and over. Im sure I could write a small program in C that could do this at least 10X more efficiently. That's 10,000 interfaces with RRD on one intel -- if you are determined to do it. I think if you are billing 10k interfaces, you can afford a 2nd intel box to check the 2nd 10,000, no? My point is that if you have sufficient clue, time, and motivation -- Today's generic PCs are capable to do many "large" tasks... --Phil -----Original Message----- From: Richard A Steenbergen [mailto:[email protected]] Sent: Tuesday, July 23, 2002 2:10 AM To: Phil Rosenthal Cc: 'Doug Clements'; [email protected] Subject: Re: PSINet/Cogent Latency On Tue, Jul 23, 2002 at 01:56:45AM -0400, Phil Rosenthal wrote: > > I don't think RRD is that bad if you are gonna check only every 5 > minutes... RRD doesn't measure anything, it stores and graphs data. The perl pollers everyone is using can barely keep up with 5 minute samples on a couple dozen routers and a few hundred interfaces, requiring "poller farms" to be distributed across a network, 'lest a box or part of the network break and you lose data. > Again, perhaps I'm just missing something, but so lets say you measure > 30 seconds late , and it thinks its on time -- So that one sample will > be higher , then the next one will be on time, so 30 seconds early for > that sample -- it will be lower. On the whole -- it will be accurate > enough -- no? "enough" is a relative term, but sure. :) > I'm not saying a hardware solution can't be better -- but it is likely > overkill compared to a few cheap intels running RRD -- assuming your > snmpd can deal with the load... What hardware... storing a few byte counters is trivial, but polling them through snmp is what is hard (never trust a protocol named "simple" or "trivial"). Creating a buffer of samples which can be periodically sampled should be easy and painless. I don't know if I call periodic ftp "painless" but its certainly a start. -- Richard A Steenbergen <[email protected]> http://www.e-gerbil.net/ras PGP Key ID: 0x138EA177 (67 29 D7 BC E8 18 3E DA B2 46 B3 D8 14 36 FE B6)
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