On 27 February 2012 17:12, Kaya Saman <kayasa...@gmail.com> wrote: > > > So I would like to build a router out of a Quad Core Xeon system. I've > selected the hardware for it already and the software barring the base OS. > > >> You want the highest cache and highest frequency cpu you can find. >> MP will not help you with routing performance at all. >> >>> > > Something like this: > > http://ark.intel.com/products/53580/Intel-Xeon-Processor-E7-8870-%2830M-Cache-2_40-GHz-6_40-GTs-Intel-QPI%29 > > 30MB cache @ 2.4GHz > > > However this does raise the question, 32bit or 64bit??? And what would be
amd64, wow I had no idea such cpu was out already, I'm not sure if anyone ever tried running openbsd on such cpu. > the benefit for having multi CPU sockets or cores??? > Almost none for "routing purposes", the kernel is big locked and all interrupts go to cpu0, so this basically means: You'll be routing packets on cpu0 *only*. But you'll get the benefit of of having the userland processes running on multiple cpus, so if you're basically routing/filtering with pf, MP won't make much difference. > --I mean for an integrated Firewall/router yes one can offload processes and > threads per core or socket Userland process will benefit from MP when running in userland, they'll get the biglock when doing a system call. You only have one process running in kernel land at-a-time. > > With this though I'm betting that a Core2Quad Q8400s CPU (which I currently > run on a FreeBSD based Mini-NAS mainframe) will be more powerful then any > Cisco SMB based router? - I can see it being more powerful then my 8xx or > 18xx series in anycase! > I don't know cisco, it's all about how much data you need to route. But if you were concerned about 75mbps, even my sun ultra 5 400mhz can do more than that. Do the math, I'd guess you can do *at least* 300mpps with any fairly modern cpu. Now do 300mpps * 1500bytes, that's your throughput for full sized packets. You may want to read this: http://www.undeadly.org/cgi?action=article&sid=20111014060000 > > Most DIY/Linux router boxes all seem to run Mini-ITX hardware on Intel ATOMs > or VIA processors or Vyatta running standard x86 Multi-core architecture for > their appliances; how does this relate to the equation? > Those are very weak processors, again, it's all about how much pps you need.
