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Re: Experiences with kprobes

Hi -

On Tue, Mar 22, 2005 at 03:13:17PM +0000, Baruch Even wrote:

> [...]  In the test with the probes I only get the cwnd up to about
> 3000, with a round trip of 300ms and delayed acking, it means
> 3000*1000/300/2 = 5000 packets per second. [...]  we get double the
> rate of ACKs which sends us to 10000 pps, at which stage the probes
> will probably affect behaviour significantly enough. [...]

But 10000 packets per second at 10000 clocks per packet (from your
previous message) represents only 1/30th of the raw capacity of a 
3 GHz CPU.  Before instrumentation, it would have been 1/60th or so.
It's strange that this 1/60th difference is enough to bog your 
test down.

- FChE

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