Re: [Qemu-devel] [PATCH] Instruction counting instrumentation for ARM, 2nd version

[Sami Kiminki]

On Fri, 2009-06-12 at 16:41 +0100, Jamie Lokier wrote:
> Sami Kiminki wrote:
> > What we would really like to see is a more general instrumentation
> > framework, not just instruction counting and not just for ARM targets.
> > The reason for this is that many measurements are so much easier to do
> > in emulated/simulated environment than in real HW (e.g. instruction
> > counting) and doing them in QEMU is way faster than using an ISA
> > interpreter such as Valgrind. Some other instrumentation examples that
> > come to my mind are cache usage efficiency analysis, branch profiling,
> > and naturally instruction and memory access tracing.
> 
> Valgrind isn't an interpreter.  It's a JIT compiler like QEMU's TCG,
> so are you sure these things are way faster in QEMU?

No, not anymore. Thanks for correcting ;)

However, what would still speak in favor of having some instrumentation
support in QEMU, is measuring things at system-level. I assume this is
pretty high in embedded system developers' wish-list.

> What might work better would be to share some code from Valgrind/Cachegrind.

Obviously.

- Sami