added load average calculations and moved the testing from main to their own cli commands

internal/load_average/loadavg.go

@@ -0,0 +1,48 @@
+package loadaverage
+
+import (
+	"math"
+	"time"
+)
+
+// Constants for calculating EMA
+
+const SAMPLE_DELAY time.Duration = time.Second * 5
+
+var (
+	ONE_MIN_ALPHA     float64 = math.Exp(-SAMPLE_DELAY.Seconds() / 60.0)  // e^(-dt/W), where dt is the sample time and W
+	FIVE_MIN_ALPHA    float64 = math.Exp(-SAMPLE_DELAY.Seconds() / 300.0) // is the target timeframe. eg.: 60 for one min
+	FIFTEEN_MIN_ALPHA float64 = math.Exp(-SAMPLE_DELAY.Seconds() / 900.0)
+)
+
+type LoadAverageInformation struct {
+	/*
+	 * Load average in the past minute
+	 */
+	Load1 float64
+	/*
+	 * Load average in the past 5 minutes
+	 */
+	Load5 float64
+	/*
+	 * Load average in the past 15 minutes
+	 */
+	Load15 float64
+
+	initialized bool // track whether this is the first measurement or not
+}
+
+func (loadAvg *LoadAverageInformation) Update(currentSample float64) {
+	if !loadAvg.initialized {
+		// Seed the initial averages with the first sample to avoid a slow ramp-up from zero
+		loadAvg.Load1 = currentSample
+		loadAvg.Load5 = currentSample
+		loadAvg.Load15 = currentSample
+		loadAvg.initialized = true
+		return
+	}
+
+	loadAvg.Load1 = loadAvg.Load1*ONE_MIN_ALPHA + currentSample*(1.0-ONE_MIN_ALPHA)
+	loadAvg.Load5 = loadAvg.Load5*FIVE_MIN_ALPHA + currentSample*(1.0-FIVE_MIN_ALPHA)
+	loadAvg.Load15 = loadAvg.Load15*FIFTEEN_MIN_ALPHA + currentSample*(1.0-FIFTEEN_MIN_ALPHA)
+}