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| author | Andrew Morton <akpm@osdl.org> | 2004-06-23 19:21:46 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2004-06-23 19:21:46 -0700 |
| commit | d2c40dc029c95a1c6bf20b2e0ba558287510d1f8 (patch) | |
| tree | 303e4e6e4630ebcac9a33f16d1e9e7b7d5b2944e /Documentation | |
| parent | c98476cb50a665294105f20e0521061767a9461b (diff) | |
| download | history-d2c40dc029c95a1c6bf20b2e0ba558287510d1f8.tar.gz | |
[PATCH] (o)profile Documentation/basic_profiling.txt updates
From: bert hubert <ahu@ds9a.nl>
Signed-off-by: bert hubert <ahu@ds9a.nl>
Signed-off-by: John Levon <levon@movementarian.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/basic_profiling.txt | 40 |
1 files changed, 22 insertions, 18 deletions
diff --git a/Documentation/basic_profiling.txt b/Documentation/basic_profiling.txt index cd3b422cc501e5..65e3dc2d4437a4 100644 --- a/Documentation/basic_profiling.txt +++ b/Documentation/basic_profiling.txt @@ -5,16 +5,19 @@ Thanks to John Levon, Dave Hansen, et al. for help writing this. <test> is the thing you're trying to measure. Make sure you have the correct System.map / vmlinux referenced! -IMHO it's easier to use "make install" for linux and hack /sbin/installkernel -to copy config files, system.map, vmlinux to /boot. + +It is probably easiest to use "make install" for linux and hack +/sbin/installkernel to copy vmlinux to /boot, in addition to vmlinuz, +config, System.map, which are usually installed by default. Readprofile ----------- -You need a fixed readprofile command for 2.5 ... either get hold of -a current version from: +A recent readprofile command is needed for 2.6, such as found in util-linux +2.12a, which can be downloaded from: + http://www.kernel.org/pub/linux/utils/util-linux/ -or get readprofile binary fixed for 2.5 / akpm's 2.5 patch from -ftp://ftp.kernel.org/pub/linux/kernel/people/mbligh/tools/readprofile/ + +Most distributions will ship it already. Add "profile=2" to the kernel command line. @@ -24,25 +27,26 @@ dump output readprofile -m /boot/System.map > captured_profile Oprofile -------- -get source (I use 0.5) from http://oprofile.sourceforge.net/ -add "idle=poll" to the kernel command line +Get the source (I use 0.8) from http://oprofile.sourceforge.net/ +and add "idle=poll" to the kernel command line Configure with CONFIG_PROFILING=y and CONFIG_OPROFILE=y & reboot on new kernel ./configure --with-kernel-support make install -One time setup (pick appropriate one for your CPU): -P3 opcontrol --setup --vmlinux=/boot/vmlinux \ - --ctr0-event=CPU_CLK_UNHALTED --ctr0-count=100000 -Athlon/x86-64 opcontrol --setup --vmlinux=/boot/vmlinux \ - --ctr0-event=RETIRED_INSNS --ctr0-count=100000 -P4 opcontrol --setup --vmlinux=/boot/vmlinux \ - --ctr0-event=GLOBAL_POWER_EVENTS \ - --ctr0-unit-mask=1 --ctr0-count=100000 +For superior results, be sure to enable the local APIC. If opreport sees +a 0Hz CPU, APIC was not on. Be aware that idle=poll may mean a performance +penalty. + +One time setup: + opcontrol --setup --vmlinux=/boot/vmlinux -start daemon opcontrol --start-daemon clear opcontrol --reset start opcontrol --start <test> stop opcontrol --stop -dump output oprofpp -dl -i /boot/vmlinux > output_file +dump output opreport > output_file + +To only report on the kernel, run opreport /boot/vmlinux > output_file + +A reset is needed to clear old statistics, which survive a reboot. |