What is OPerf and Perf?

97. What is Operf?
  operf - Performance profiler tool for Linux
   Operf is the profiler tool provided with OProfile. Operf uses the
     Linux Performance Events Subsystem and, thus, does not require the
     obsolete oprofile kernel driver.

     By default, operf uses <current_dir>/oprofile_data as the session-dir
     and stores profiling data there.  You can change this by way of the
     --session-dir option. The usual post-profiling analysis tools such as
     opreport(1) and opannotate(1) can be used to generate profile
     reports. Unless a session-dir is specified, the post-processing
     analysis tools will search for samples in <current_dir>/oprofile_data
     first. If that directory does not exist, the post-processing tools
     use the standard session-dir of /var/lib/oprofile.

     Statistics, such as total samples received and lost samples, are
     written to the operf.log file that can be found in the
        <session_dir>/samples directory

       
98. What is Perf?
Perf is a profiler tool for Linux 2.6+ based systems that abstracts away
CPU hardware differences in Linux performance measurements and presents
a simple commandline interface. Perf is based on the perf_events interface
 exported by recent versions of the Linux kernel.
 One example about how to use Perf on Linux (genoa here):
 perf stat -d ./executable_name
 perf stat -d ./gcc-ld-global-var-benchmark