Interrupt latency in L4Linux

Adam Lackorzynski adam at
Tue Aug 23 13:11:25 CEST 2005

On Tue Aug 23, 2005 at 09:59:23 +0200, fabs0028 at wrote:
> well i 'd like to measure the latency of the interrupts in l4linux, between the
> moment it is triggered in fiasco and the moment it is aknowledged in the
> top-halves of linux.

I guess the simplest way to do this in software is to write a jdb trace
entry in the interupt handler and another on the in the userland code
where it's handled. The jdb trace view will show you the TSC differences
between the two log entries (cycle through the different modes). This
will give you a little overhead of course, which you may want to

Adam                 adam at

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