Linux-2.4.latest
PACKET_MMAP
PCAP_FRAMES=max for tcpdump-3.8/libpcap-0.8 (from http://public.lanl.gov/cpw/)
e1000 driver
2 * Xeon 2800 MHz, 512 KB L2
1 GB RAM
70 GB HW RAID-0 on SmartArray 5i
2 * 2 port Intel GigE cards (only using 1 per card for the testing purposes)
Capturing all packets and writting to /dev/null causes more packet drops than
writting to hard drives (approx 40,000 packets/sec of 70 bytes for couple of
minutes). I will have a comparision between those figures in a day or two,
but /dev/null was well over SCSI hard drives. I thought writting (even
multiple of them simultaneously) to /dev/null should be faster than fastest
SCSI drives out there :) Interesting.
(And yes I see plenty of "errors", "dropped", and "overruns" in ifconfig stats
on those interfaces. %system is over 80%, and tcpdump goes to "D" state many
times. Simon Kirby suggested to use irq-smp_affinity to see if that helps for
reducing %system time. A well optimised e1000 would definitely help as tg3
does it very well.)
I mean to test this /dev/null behavior on 2 tg3 driver configuration perhaps
in couple of days time. (But the 2 tg3 cards with out-of-the-box NAPI support
on 2.4.latest is able to not to loose a single packet even while writting to
hard drives, then I didn't care to test it on /dev/null)
BTW I found 2.5.51 backport of e1000 NAPI support at
http://havoc.gtf.org/lunz/linux/net/
Anyone knows of a recent backport or improved one for 2.4.latest (including
2.4.21-pre5 or -pre6). Patches for testing or URL is welcome.
Thanks
-- Hari harisri@bigpond.com- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Mar 23 2003 - 22:00:30 EST