Markus Kolb wrote: > Am 2015-02-19 10:51, schrieb Peter Hessler: > > > > :choose the CPU with higher Frequency and less cores or for a CPU with > > :lower frequency but more cores? > > > > Higher frequency. Period. > > > > Right now, network and PF processing is limited to CPU0. You want that > > as fast as possible. > > > > Additionally, you want as fast memory transfers (from CPU to RAM) as > > possible. > > > > That will give you the most performance. > > Is it as simple as "Higher frequency."? > Shouldn't there be a view on the instruction sets mostly used in network > traffic handling and cycle usage of these instructions? > Or is this equivalent at the up-to-date processors? > If not, it is possible that lower frequency is faster.
Every iX-3xxx is about the same in terms of IPC. Same for iX-4xxx, etc. But some models do have AES-NI and some don't. This will clearly matter if you're also doing IPsec or so. Also, last I checked for desktop chips, i3 was 2 core hyperthreaded (4 threads) while i5 was quad core not-hyper (still 4 threads). OpenBSD still isn't really aware of hyperthreaded, so you'll get better, more consistent performance from the i5. The i7 then goes to four cores, 8 threads, which is less than ideal for openbsd. There's also some variation in the availability of various VT extensions. Last two points probably don't matter much for a pure firewall passing packets, but the few hundred mhz gained may not be a worthwhile trade for flexibilty if you ever intend to repurpose the box.
