Re: [RFC PATCH 1/3] Unified trace buffer

[Steven Rostedt]

On Thu, 25 Sep 2008, Mathieu Desnoyers wrote:

> * Steven Rostedt (rostedt@xxxxxxxxxxx) wrote:
> > 
> > On Thu, 25 Sep 2008, Mathieu Desnoyers wrote:
> > > The problem with sched_clock is that it gives a 1 HZ timestamp accuracy
> > > for events happening across different CPUs. Within this 1 HZ range, it
> > > uses the TSC and clip when it reaches a max. Good enough for scheduler
> > > or for tracing events on a single CPU, but I think it is not exactly
> > > what we need to reorder events happening across CPUs.
> > > 
> > 
> > 
> > Hmm,
> > 
> > sched_clock gives ns accuracy unless the tsc is disabled. And in that 
> > case, we don't have any CPU clock :-/
> > 
> 
> Even on architectures with non-synchronized TSCs ?

Yep, even on those ;-)

-- Steve
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