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Re: [RFC][PROTO][PATCH -tip 0/7] kprobes: support jump optimization on x86


On Wed, Apr 08, 2009 at 12:10:56PM +0200, Ingo Molnar wrote:
> 
> * Masami Hiramatsu <mhiramat@redhat.com> wrote:
> 
> > > But can we consider it as a small problem, assuming that kprobes 
> > > are rarely intended for a massive use in once? I guess that 
> > > usually, not a lot of functions are probed simultaneously.
> > 
> > Hm, yes and no, systemtap may use massive kprobes, because it 
> > supports "wildcard" probes. However, optimizing in default may be 
> > acceptable.
> 
> I'm curious: what is the biggest kprobe count you've ever seen, in 
> the field? 1000? 10,000? 100,000? More?

The limit is iirc how much memory the gcc compiling the probes program
consumes before running out of swap space.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.


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