35 lines
889 B
Go
35 lines
889 B
Go
package tracer
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import (
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"time"
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"golang.org/x/sys/windows"
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"gopkg.in/DataDog/dd-trace-go.v1/internal/log"
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)
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// This method is more precise than the go1.8 time.Now on Windows
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// See https://msdn.microsoft.com/en-us/library/windows/desktop/hh706895(v=vs.85).aspx
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// It is however ~10x slower and requires Windows 8+.
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func highPrecisionNow() int64 {
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var ft windows.Filetime
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windows.GetSystemTimePreciseAsFileTime(&ft)
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return ft.Nanoseconds()
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}
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func lowPrecisionNow() int64 {
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return time.Now().UTC().UnixNano()
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}
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var now func() int64
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// If GetSystemTimePreciseAsFileTime is not available we default to the less
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// precise implementation based on time.Now()
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func init() {
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if err := windows.LoadGetSystemTimePreciseAsFileTime(); err != nil {
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log.Warn("Unable to load high precison timer, defaulting to time.Now()")
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now = lowPrecisionNow
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} else {
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now = highPrecisionNow
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}
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}
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