If an MSR based monitor is run in parallel this is not needed. This is the
default case on all/most Intel machines.
But when only sysfs info is read via cpupower monitor -m Idle_Stats (typically
the case for non root users) or when other monitors are PCI based (AMD),
Idle_Stats, read from sysfs can be totally bogus:
cpupower monitor -m Idle_Stats
PKG |CORE|CPU | POLL | C1-N | C3-N | C6-N
0| 0| 0| 0.00| 0.00| 0.24| 99.81
0| 0| 32| 0.00| 0.00| 0.00| 100.7
...
0| 17| 20| 0.00| 0.00| 0.00| 173.1
0| 17| 52| 0.00| 0.00| 0.07| 173.0
0| 18| 68| 0.00| 0.00| 0.00| 0.00
0| 18| 76| 0.00| 0.00| 0.00| 0.00
...
With the -c option all cores are woken up and the kernel
did update cpuidle statistics before reading out sysfs.
This causes some overhead. Therefore avoid if possible, use
if needed:
cpupower monitor -c -m Idle_Stats
PKG |CORE|CPU | POLL | C1-N | C3-N | C6-N
0| 0| 0| 0.00| 0.00| 0.00| 100.2
0| 0| 32| 0.00| 0.00| 0.00| 100.2
...
0| 8| 8| 0.00| 0.00| 0.00| 99.82
0| 8| 40| 0.00| 0.00| 0.00| 99.81
0| 9| 24| 0.00| 0.00| 0.00| 100.3
0| 9| 56| 0.00| 0.00| 0.00| 100.2
0| 16| 4| 0.00| 0.00| 0.00| 99.75
0| 16| 36| 0.00| 0.00| 0.00| 99.38
...
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix minor warnings reported with GCC 4.6:
* The sysfs_write_file function is unused - remove it.
* The pr_mon_len in the print_header function is unsed - remove it.
Signed-off-by: Palmer Cox <p@lmercox.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Instead of printing something non-formatted to stdout, call
man(1) to show the man page for the proper subcommand.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
This allows for example:
cpupower -c 2-4,6 monitor -m Mperf
|Mperf
PKG |CORE|CPU | C0 | Cx | Freq
0| 8| 4| 2.42| 97.58| 1353
0| 16| 2| 14.38| 85.62| 1928
0| 24| 6| 1.76| 98.24| 1442
1| 16| 3| 15.53| 84.47| 1650
CPUs always get resorted for package, core then cpu id if it could get read out
(or however you name these topology levels...).
Still this is a nice way to keep the overview if a test binary is bound to
a specific CPU or if one wants to show all CPUs inside a package or similar.
Still missing: Do not measure not available cores to reduce the overhead
and achieve better results.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Before, checking for offlined CPUs was done dirty and
it was checked whether topology parsing returned -1 values.
But this is a valid case on a Xen (and possibly other) kernels.
Do proper online/offline checking, also take CONFIG_HOTPLUG_CPU
option into account (no /sys/devices/../cpuX/online file).
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
CPU power consumption vs performance tuning is no longer
limited to CPU frequency switching anymore: deep sleep states,
traditional dynamic frequency scaling and hidden turbo/boost
frequencies are tied close together and depend on each other.
The first two exist on different architectures like PPC, Itanium and
ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will
only run most efficiently if CPU and GPU has proper power management
in place.
Users and Developers want to have *one* tool to get an overview what
their system supports and to monitor and debug CPU power management
in detail. The tool should compile and work on as many architectures
as possible.
Once this tool stabilizes a bit, it is intended to replace the
Intel-specific tools in tools/power/x86
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
