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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Regarding global BGP community values
Hmm. In the 'SNMPSTATD' monitoring I use (it's in the near plans) to monitor not _FREE MEMORY but _THE BIGGEST PIECE OF THE FREE MEMORY_. It's the most critical argument. If it is less than 128K, 'config' command do not work; if it is less than 1500 bytes, nothing works at all -:) > > AFAIK, there is some more memory wasting and dangerous feature in > current (at least it was so year ago) implementation of memory allocation > subsystem in Cisco: when you are going below some magic value > (for defaultless routers usualy below 10-8 megs) and have even > moderate BGP activity, very soon (less then a day) you will be out of > memory even in the presence of this 8-10 megs of free memory because your largest fragment will be very close to 0. > As I was told several years ago this is fundamental "feature" of > memory allocation implementation (poor fragmentation resistance with low memory and lots of small alloc's/free's). The fundamental feature for the REAL-TIME device (such as ROUTER) should be a lot of HOT-DOG mechanisms preventing /at least/ lost of the control over the device. In case of such _voracious_ processes (as BGP is) it should be used any mechanism preventing it from catching all existing resources (CPU and MEMORY in our case).
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