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Re: Poor scaling
On 08/08/2016 11:38 PM, Avi Kivity wrote:
> Are entire probes serialized, or just individual variables? If the
> latter, perhaps you can detect that an array's index is always tid(),
> remove that index, and convert the global variable to a thread-local one
> (with an exception for begin and end probes).
I think I'd rather see this explicit declared on the global itself,
instead of treating tid() specially. Something like the proposed percpu
globals:
https://sourceware.org/bugzilla/show_bug.cgi?id=10795
The challenge is how to allocate and free that per-task memory, and how
to look up that memory from arbitrary probe context. It's possible,
just not entirely trivial.