The source code of this class is located at CpuSampleFrequencyAnalyzer.hpp.

CpuSampleFrequencyAnalyzer is an analyzer used to find out which symbol names appear most frequently.

There two different rankings:

• Top Inclusive Symbol Names: The functions that uses the most cpu, include the functions it called
• Top Exclusive Symbol Names: The functions that uses the most cpu, not include the functions it called

Functions in CpuSampleFrequencyAnalyzer

setInclusiveTraceLevel

Set how many levels should be considered for inclusive sampling, the default value is 3. For example:

- a
  - b
  - c
  - d
  - e
(e calls d calls c calls b calls a)

If inclusive trace level is 3, then [a, b, c, d] will be treated as inclusive sample.

getResult

Generate the result. The result type is defined as:

using SymbolNameAndCountType = std::pair<std::shared_ptr<SymbolName>, std::size_t>;

class ResultType {
public:
	const std::vector<SymbolNameAndCountType>& getTopInclusiveSymbolNames() const&;
	const std::vector<SymbolNameAndCountType>& getTopExclusiveSymbolNames() const&;
	std::size_t getTotalSampleCount() const;
};

Example

Example code: Main.cpp

Run example:

sh run.sh a.out 10000

The output is like:

top 16 inclusive symbol names:
No. Overhead Samples SymbolName
  1     1.71   50964 make(int, NodePool&)
  2     0.50   14860 apr_palloc
  3     0.47   13905 main._omp_fn.0
  4     0.30    8969 GOMP_parallel
  5     0.26    7776 vmxarea
  6     0.22    6496 Node::check() const
  7     0.01     279 apr_pool_clear
  8     0.01     185 main
  9     0.01     185 __libc_start_main
 10     0.00      47 apr_allocator_destroy
 11     0.00      25 apr_pool_destroy
 12     0.00      11 __munmap
 13     0.00       2 __vsprintf_chk
 14     0.00       2 mmap
 15     0.00       1 _IO_default_xsputn
 16     0.00       1 vfprintf

top 11 exclusive symbol names:
No. Overhead Samples SymbolName
  1     0.50   14860 apr_palloc
  2     0.23    6793 make(int, NodePool&)
  3     0.19    5749 Node::check() const
  4     0.04    1122 main._omp_fn.0
  5     0.01     279 apr_pool_clear
  6     0.00      47 apr_allocator_destroy
  7     0.00      25 apr_pool_destroy
  8     0.00      11 __munmap
  9     0.00       2 mmap
 10     0.00       1 _IO_default_xsputn
 11     0.00       1 vfprintf