> I've never heard about someone using the flat format.
I'm not surprised about that: it looks like it's basically just the same as fractal, except without
combining the similar parts of call chains together. Doesn't seem usefulĀ at all. And that also isn't
what I want. (Sidenote: I'd have expected something named "flat" to actually show me a normal
flat profile; it seems a bit odd that perf report can't actually show a normal flat profile when
callgraph info was collected.)
I just like to see a list of the *direct* callers and callees of every function. (having both easily
available is an important component). I don't actually want to be shown every unique complete
call-chain starting from the named function: it's just too much data, and yet simultaneously not
enough, since it doesn't show callees.
I think the gprof docs explain its format pretty well, and that's basically exactly what I want to
see. It's a nice, concise, easy-to-understand summarization of the data that usually has enough
information to figure out where the problem is.
Or, heck, if you get callgrind output conversion working, kcachegrind also presents the data in
this way, so you wouldn't even have to implement the gprof-like output format. :)
Or similar callgraph visualization support in perf itself would be nice (including filtering options, highlighting the nodes based on CPU used by given node and the nodes called by it etc).
Finding a profiler that works, damnit
Posted Apr 4, 2010 12:44 UTC (Sun) by chantecode (subscriber, #54535)
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I really like this. We may indeed want to support it.
Finding a profiler that works, damnit
Posted Apr 5, 2010 1:39 UTC (Mon) by foom (subscriber, #14868)
[Link]
Check out the google-perftools' pprof's "gv" command; it's also pretty nice. (although I still usually
prefer kcachegrind's interactive viewer)