moby/daemon/stats/collector_windows.go
Ian Campbell 115f91d757 Correct CPU usage calculation in presence of offline CPUs and newer Linux
In https://github.com/torvalds/linux/commit/5ca3726 (released in v4.7-rc1) the
content of the `cpuacct.usage_percpu` file in sysfs was changed to include both
online and offline cpus. This broke the arithmetic in the stats helpers used by
`docker stats`, since it was using the length of the PerCPUUsage array as a
proxy for the number of online CPUs.

Add current number of online CPUs to types.StatsJSON and use it in the
calculation.

Keep a fallback to `len(v.CPUStats.CPUUsage.PercpuUsage)` so this code
continues to work when talking to an older daemon. An old client talking to a
new daemon will ignore the new field and behave as before.

Fixes #28941.

Signed-off-by: Ian Campbell <ian.campbell@docker.com>
2017-03-10 10:24:33 +00:00

19 lines
548 B
Go

// +build windows
package stats
// platformNewStatsCollector performs platform specific initialisation of the
// Collector structure. This is a no-op on Windows.
func platformNewStatsCollector(s *Collector) {
}
// getSystemCPUUsage returns the host system's cpu usage in
// nanoseconds. An error is returned if the format of the underlying
// file does not match. This is a no-op on Windows.
func (s *Collector) getSystemCPUUsage() (uint64, error) {
return 0, nil
}
func (s *Collector) getNumberOnlineCPUs() (uint32, error) {
return 0, nil
}