On 15-10-25 03:46 AM, Some Developer wrote:
I'm just wondering what hardware spec I'd need push 20 gigabits of
network traffic on an OpenBSD server?
Short answer: It's not generally possible today, at least for your use
case.
Medium answer: Contact Esdenera Networks to find out. They manage to
do it somehow. I'm sure they'll be happy to make it happen for you in
exchange for suitable amounts of money...
Longer answer:
Network performance research numbers have presented by gnn at various
conferences over the last year or so, and they consistently showed that
OpenBSD, while performing well for a single-threaded stack, fell badly
behind in multi-core, and wasn't able to keep up to 10Gbps. The OpenBSD
team is (currently, AFAIK) working on making the network stack
multi-threaded, or at least not giant-locked, which should (eventually)
dramatically increase performance scalability.
On top of that, there are substantial optimizations possible; research
in the FreeBSD camp (and experience under OpenBSD as well) has shown
that seemingly-similar hardware can perform radically differently.
Drivers make a big difference.
You talk about storing the data - *writing* data to disk at 10Gbps
(sustained) is currently in the realm of high-energy physics, with
multi-million-dollar budgets for the storage arrays. A 7200rpm disk can
charitably be said to write at up to 100MBytes/sec, but that's not
necessarily sustained speed, so minimum 10-unit array assuming 100%
ideal throughput, which doesn't actually exist in the real world. More
likely you'd have to buy a large HDS array to get that kind of
throughput. Plus, that's about 2.5PB (yes, PETAbytes) of data every
month. Are you building this for the NSA?!?
You do realize that this means you're now trying to push *30* Gbits/sec
on a single server, right? (10 in, 10 out, 10 logged) Even Netflix, who
spend a ridiculous amount of time doing optimization, have only recently
gotten FreeBSD servers with tons of custom code and tweaks to pass the
65Gbps-per-socket mark.
Lastly, Gbits/sec isn't the bottleneck. The bottleneck is
packets-per-second. If you're pushing 10Gbps worth of 1500-byte
packets, then this is possible today. (Not sure about 30Gbps.) If
you're trying to push 10Gbps worth of 64-byte packets on commodity
hardware, forget about this pipe dream for another few years until the
fully-MP network stack is finished and optimized.
Good luck... but you might want to consider doing this on a Juniper MX
series or Cisco ASR instead - those platforms can at least maybe do the
tunnelling part for around $250k, then feed the output into a 10GE
switch with port mirroring (~$10k), then a Network Flight Recorder or
similar to actually capture that much data (~$150k).
-Adam
