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opcontrol—stop (stops collecting the data)
opcontrol—stop (stops collecting the data)


opcontrol—shutdown (clears the data)
opcontrol—shutdown (Stops the demon)

opcontrol -reset (clears the profile data which was stored in the sample file given)


== See also==
== See also==

Revision as of 07:06, 1 March 2013

Original author(s)John Levon
Initial release2001
Written inC
Operating systemLinux
Platformcross-platform
Typeprofiler
LicenseGPL
Websitehttp://oprofile.sourceforge.net/news/

OProfile - system-wide statistical profiling tool for Linux. Written by John Levon in 2001 for Linux kernel version 2.4 after his M.Sc. project.[1] Consists of kernel module, user-space daemon and several user-space tools.

This tool is capable of profiling entire system or its parts, from interrupt routines or drivers, to user-space processes. It has low overhead.

Most portable mode of oprofile uses system timer to generate sampling interrupts (events). Less portable mode allows hardware performance counters to be used for sampling events generationed on several processor architectures. In Linux 2.2/2.4 only 32-bit x86 and IA64 are supported; in Linux 2.6 there is wider support: x86 (32 and 64 bit), DEC Alpha, MIPS, ARM, sparc64, ppc64, AVR32.

Call graphs are supported only on x86 and ARM.

In 2012 it was recognized by IBM's engineers as one of two most commonly used performance counter monitor profiling tools on Linux; the other was perf tool.[2]

User-space tools

  • opcontrol is used to start and stop the daemon, which collects profiling data. This data is periodically saved to the /var/lib/oprofile/samples directory.
  • opreport shows basic profiling data. 'opannotate' can produce annotated sources or assembly.
  • opgprof converts from oprofile data into gprof-compatible format.[3]

Example:

opcontrol—start ( If there are any issues in starting like—vm-linux just follow the instructions)
run <example>
opcontrol—dump
opreport -l <example> > <outputfile> 
opcontrol—stop (stops collecting the data)
opcontrol—shutdown (Stops the demon)
opcontrol -reset (clears the profile data which was stored in the sample file given)

See also

References

  1. ^ Interview: John Levon, 11 Nov 2001 // KernelTrap: "John Levon, the author of OProfile"
  2. ^ A. Zanella, R. Arnold. Evaluate performance for Linux on POWER. Analyze performance using Linux tools, 12 Jun 2012 // IBM DeveloperWorks Technical library
  3. ^ http://oprofile.sourceforge.net/doc/tools-overview.html