When fetching stats on all processes at once there's a non-trivial amount of
time spent in the `BootTime` call. But since this value should never change
during a live process, we can use a cached version for all subsequent calls.
The value for `ClockTicks` is defined as `100` by the Linux kernel for
all currently supported architectures in Go. Therefore, there is no need
to define this constant for each architecture separately.
This fixes #260.
Signed-off-by: Thomas Hipp <thomashipp@gmail.com>
Instead of hard-coding the page size for linux systems, use Go's
`Getpagesize` function.
This resolves #258.
Signed-off-by: Thomas Hipp <thipp@suse.de>
* on virtualized host, this may happen.
* but we may have a value from parsing `/proc/cpuinfo`
* in this case, we do not return the error if we fail to extra
a value from `cpufreq/cpuinfo_max_freq`
* resolve #249
* in `cpu_windows.go`, `Mhz` is the value of `MaxClockSpeed`
* on Linux platform, the `Mhz` value is extracted from `/proc/cpuinfo`
which reflects the current clock speed; treat this as the fallback
value instead
* read from `cpufreq/cpuinfo_max_freq` under sysfs to get the
maximum clock speed for `Mhz`, just like for Windows platform
* also fix the path to `cpu.CoreID` value; the filename is `core_id`
* for Darwin, it is a minor tweak for readability: the value
returned is in Hz, so using a variable named 'hz' makes more
sense than 'mhz'
* for Linux, the unit is in kHz so we need to divide the value
from `cpuinfo_max_freq` by 10^3 to get MHz (see
cpu-freq/user-guide.txt of the kernel documentation)
This enables using gopsutil in a codebase that gets built on other OSes
than the ones supported. Instead of a build failure as before, due to
the build tags, gopsutil will now throw an "not implemented" runtime
error.
Fixes #234.