[FIXED] PS test to reduce failures in some situations

Added garbage collection before each capture method and bump the
delta threshold to 1MB.

Resolves #310

server/pse/pse_test.go

@@ -17,6 +17,8 @@ func TestPSEmulation(t *testing.T) {
 	var rss, vss, psRss, psVss int64
 	var pcpu, psPcpu float64
 
+	runtime.GC()
+
 	// PS version first
 	pidStr := fmt.Sprintf("%d", os.Getpid())
 	out, err := exec.Command("ps", "o", "pcpu=,rss=,vsz=", "-p", pidStr).Output()
@@ -28,6 +30,8 @@ func TestPSEmulation(t *testing.T) {
 	psRss *= 1024 // 1k blocks, want bytes.
 	psVss *= 1024 // 1k blocks, want bytes.
 
+	runtime.GC()
+
 	// Our internal version
 	ProcUsage(&pcpu, &rss, &vss)
 
@@ -45,7 +49,7 @@ func TestPSEmulation(t *testing.T) {
 		if delta < 0 {
 			delta = -delta
 		}
-		if delta > 512*1024 { // 512k
+		if delta > 1024*1024 { // 1MB
 			t.Fatalf("RSSs did not match close enough: %d vs %d", rss, psRss)
 		}
 	}

server/pse/pse_windows_test.go

@@ -6,6 +6,7 @@ package pse
 import (
 	"fmt"
 	"os/exec"
+	"runtime"
 	"strconv"
 	"strings"
 	"testing"
@@ -26,7 +27,7 @@ func checkValues(t *testing.T, pcpu, tPcpu float64, rss, tRss int64) {
 		if delta < 0 {
 			delta = -delta
 		}
-		if delta > 200*1024 { // 200k - basically sanity check
+		if delta > 1024*1024 { // 1MB
 			t.Fatalf("RSSs did not match close enough: %d vs %d", rss, tRss)
 		}
 	}
@@ -36,10 +37,14 @@ func TestPSEmulationWin(t *testing.T) {
 	var pcpu, tPcpu float64
 	var rss, vss, tRss int64
 
+	runtime.GC()
+
 	if err := ProcUsage(&pcpu, &rss, &vss); err != nil {
 		t.Fatalf("Error:  %v", err)
 	}
 
+	runtime.GC()
+
 	imageName := getProcessImageName()
 	// query the counters using typeperf
 	out, err := exec.Command("typeperf.exe",
@@ -70,6 +75,8 @@ func TestPSEmulationWin(t *testing.T) {
 
 	checkValues(t, pcpu, tPcpu, rss, tRss)
 
+	runtime.GC()
+
 	// Again to test caching
 	if err = ProcUsage(&pcpu, &rss, &vss); err != nil {
 		t.Fatalf("Error:  %v", err)