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

[Mathieu Desnoyers]

* 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 ?

Mathieu

> 
> -- Steve
> 

-- 
Mathieu Desnoyers
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