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SubjectRe: [PATCH 00/21] perf, c2c: Add new tool to analyze cacheline contention on NUMA systems
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On Mon, Feb 10, 2014 at 10:29 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> On Mon, Feb 10, 2014 at 12:28:55PM -0500, Don Zickus wrote:
>> The data output is verbose and there are lots of data tables that interprit the latencies
>> and data addresses in different ways to help see where bottlenecks might be lying.
>
> Would be good to see what the output looks like.
>
> What I haven't seen; and what I would find most useful; is using the IP
> + dwarf info to map it back to a data structure member.
>
> Since you're already using the PEBS data-source fields, you can also
> have a precise IP. For many cases its possible to reconstruct the exact
> data member the instruction is modifying.
>
The tool already uses precise=2 to get the precise IP.

To get from IP to data member, you'd need some debug info which is not
yet emitted
by the compiler.

> At that point you can do pahole like output of data structures, showing
> which members are 'hot' on misses etc.


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