collector: perf unable to load symbols from some .so libraries causes some LBR stacks contain unresolvable addresses

pszostek / cp

C. profiler

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collector: perf unable to load symbols from some .so libraries causes some LBR stacks contain unresolvable addresses #12

Open xs-exp opened 8 years ago

xs-exp commented 8 years ago

Example:

4382,0,0,0,0,0
4383,37913,29923,10,33958,10
4384,37913,34003,10,29974,10
4385,37913,30209,10,10528,10
4386,37913,10682,10,5056,10
4387,37913,10697,10,13297,10
4388,37913,13304,10,4944,10
4389,0,0,0,0,0

**1. LBR stack is too short (some filtering seems to be happening)

Line 4386 has no follow-up**

xs-exp commented 8 years ago

Need to check if NEAR_TAKEN is the problem (as in "near" is the problem)

xs-exp commented 8 years ago

perf is not loading symbols from an Intel library: libiomp5.so these are later reported as raw addresses without a DSO or base

xs-exp commented 8 years ago

Workaround provided - unknown addresses are zeroed in perf.2016. But, all samples from libraries that perf can't read will be lost with this workaround (which could be a lot)