Messages in this thread | | | Date | Mon, 19 Jun 2006 16:47:49 +0200 (CEST) | From | Jesper Dangaard Brouer <> | Subject | Re: Network performance degradation from 2.6.11.12 to 2.6.16.20 |
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>> Harry Edmon <harry@atmos.washington.edu> 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. <cut>
Hi Harry
Can you check which "high-res timesource" you are using?
In the kernel log look for: kernel: Using tsc for high-res timesource kernel: Using pmtmr for high-res timesource
I have experinced some network performance degradation when using the "pmtmr" timesource, on a Opteron AMD system. It seems that the default timesource change between 2.6.15 to 2.6.16.
If you use "pmtmr" try to reboot with kernel option "clock=tsc".
On my Opteron AMD system i normally can route 400 kpps, but with timesource "pmtmr" i could only route around 83 kpps. (I found the timer to be the issue by using oprofile).
Cheers, Jesper Brouer
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