Re: Linux 2.6.9 pktgen module causes INIT process respawning and sickness

From: Lincoln Dale
Date: Sun Nov 21 2004 - 22:50:05 EST


Jeff,

you're using commodity x86 hardware. what do you expect?

while the speed of PCs has increased significantly, there are still significant bottlenecks when it comes to PCI bandwidth, PCI arbitration efficiency & # of interrupts/second.
linux ain't bad -- but there are other OSes which still do slightly better given equivalent hardware.

with a PC comes flexibility.
that won't match the speed of the FPGAs in a Spirent Smartbits, Agilent RouterTester, IXIA et al ...


cheers,

lincoln.

At 09:06 AM 20/11/2004, Jeff V. Merkey wrote:

Additionally, when packets sizes 64, 128, and 256 are selected, pktgen is unable to achieve > 500,000 pps (349,000 only on my system).
A Smartbits generator can achieve over 1 million pps with 64 byte packets on gigabit. This is one performance
issue for this app. However, at 1500 and 1048 sizes, gigabit saturation is achievable.
Jeff

Jeff V. Merkey wrote:


With pktgen.o configured to send 123MB/S on a gigabit on a system using pktgen set to the following parms:

pgset "odev eth1"
pgset "pkt_size 1500"
pgset "count 0"
pgset "ipg 5000"
pgset "src_min 10.0.0.1"
pgset "src_max 10.0.0.254"
pgset "dst_min 192.168.0.1"
pgset "dst_max 192.168.0.254"

After 37 hours of continual packet generation into a gigabit regeneration tap device,
the server system console will start to respawn the INIT process about every 10-12
hours of continuous packet generation.

As a side note, this module in Linux is extremely useful and the "USE WITH CAUTION" warnings
are certainly will stated. The performance of this tool is excellent.

Jeff

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/