On Fri, 16 Jun 2006 09:01:23 -0700
Harry Edmon <[email protected]> wrote:
> I have a system with a strange network performance degradation from
> 2.6.11.12 to most recent kernels including 2.6.16.20 and 2.6.17-rc6.
> The system is has Dual single core Xeons with hyperthreading on. The
> application is the LDM system from UCAR/Unidata
> (http://www.unidata.ucar.edu/software/ldm). This system requests
> weather data from a variety of systems using RPC calls over a reserved
> TCP port (388), puts them into a memory mapped queue file, and then
> sends the data out to a variety of downstream requesting systems, again
> using RPC calls. When the load is heavy, the 2.6.16.20 kernel falls way
> behind with the data ingestion. The 2.6.11.12 kernel does not. I have
> tried an experiment with a 2.6.17-rc6 system where it just does the
> ingestion, and not the downstream distribution, and it is able to keep
> up. I would really appreciate any pointers as to where the problem may
> be and how to diagnose it. I have attached the config files from both
> kernels and the sysctl.conf file I am using. I have also included the
> output from "netstat -s" on the 2.6.16.20 system during a time when it
> was having problems.
>
(added netdev)
A quick grep indicates that it isn't using TCP_NODELAY - we've had problems
with that in the past.
Perhaps a tcpdump of the net traffic will help to determine what's going on.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
