On Mon, Oct 6, 2008 at 9:37 AM, Peter Van Epp <[EMAIL PROTECTED]> wrote: > <snip> >> >> Since he's using the memory cache and a pretty sizeable loop count, >> it's probably not disk I/O. I'm guessing most of it is overhead of >> doing 500K write()'s per second. >> >> When you're getting 995Mbps, I doubt your average packet size is 102 >> bytes like Jeff's. If it is, then I'd love to hear more about your >> setup (kernel version, tuning, hardware, etc) >> > > You are correct, thats with 9K jumbo frames (these are HPC people, they > don't do no stinkin small frames :-)). At 1500 it drops to about 650 megs. > The default untuned kernel 35 megabits was also 9k jumbo frames. Some time > I'll poke at why the drop at a 1500 MTU (perhaps something in tcp, perhaps > interrupt load perhaps something else). The bottom line is going fast > is hard with lots and lots of non obvious places that can bite you :-).
Actually, I'd look into why you're only getting 995Mbps w/ jumbo frames: 650Mbps * 1024 * 1024 / 8bits/byte / 1514 bytes/packet = 56,272pps 995Mbps * 1024 * 1024 / 8bits/byte / 9014 bytes/packet = 14,468pps Honestly, neither of these numbers are that great IMHO... you should be able to do 100,000pps on most hardware nowadays. -- Aaron Turner http://synfin.net/ http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & Windows They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety. -- Benjamin Franklin ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Tcpreplay-users mailing list Tcpreplay-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tcpreplay-users Support Information: http://tcpreplay.synfin.net/trac/wiki/Support
