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-Basic kernel profiling
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-======================
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-
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-
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-These instructions are deliberately very basic. If you want something clever,
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-go read the real docs ;-)
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-
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-Please don't add more stuff, but feel free to
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-correct my mistakes ;-) (mbligh@aracnet.com)
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-
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-Thanks to John Levon, Dave Hansen, et al. for help writing this.
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-
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-``<test>`` is the thing you're trying to measure.
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-Make sure you have the correct ``System.map`` / ``vmlinux`` referenced!
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-
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-It is probably easiest to use ``make install`` for linux and hack
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-``/sbin/installkernel`` to copy ``vmlinux`` to ``/boot``, in addition to
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-``vmlinuz``, ``config``, ``System.map``, which are usually installed by default.
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-
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-Readprofile
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------------
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-
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-A recent ``readprofile`` command is needed for 2.6, such as found in util-linux
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-2.12a, which can be downloaded from:
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-
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- http://www.kernel.org/pub/linux/utils/util-linux/
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-
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-Most distributions will ship it already.
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-
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-Add ``profile=2`` to the kernel command line.
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-
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-Some ``readprofile`` commands::
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-
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- clear readprofile -r
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- <test>
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- dump output readprofile -m /boot/System.map > captured_profile
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-
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-Oprofile
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---------
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-
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-Get the source (see Changes for required version) from
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-http://oprofile.sourceforge.net/ and add ``idle=poll`` to the kernel command
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-line.
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-
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-Configure with ``CONFIG_PROFILING=y`` and ``CONFIG_OPROFILE=y`` & reboot on new kernel::
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-
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- ./configure --with-kernel-support
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- make install
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-
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-For superior results, be sure to enable the local APIC. If opreport sees
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-a 0Hz CPU, APIC was not on. Be aware that idle=poll may mean a performance
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-penalty.
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-
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-One time setup::
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-
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- opcontrol --setup --vmlinux=/boot/vmlinux
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-
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-Some ``opcontrol`` commands::
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-
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- clear opcontrol --reset
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- start opcontrol --start
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- <test>
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- stop opcontrol --stop
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- dump output opreport > output_file
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-
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-To only report on the kernel, run ``opreport -l /boot/vmlinux > output_file``
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-
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-A reset is needed to clear old statistics, which survive a reboot.
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