Fixed ballast test cases by using cross-platform lib (#61)

* Fixed ballast test cases by using  cross-platform lib

The ballast test case unreliable across platforms so had to remove it.
It'll be replaced with an external test case as leveraging the
performance testbed.

The latest version was working on Linux and macOS laptops but had a hard
time on Travis CI. It seems the only reliable way to test ballast is to
spin up an external collector process and monitor it's memory usage.
This will be implemented as part one of the perf testbed cases.

Author: owais

cmd/occollector/app/collector/collector_test.go

@@ -18,14 +18,9 @@ package collector
 import (
 	"net"
 	"net/http"
-	"os"
-	"runtime"
 	"testing"
 
-	stats "github.com/guillermo/go.procstat"
-
 	"github.com/open-telemetry/opentelemetry-service/internal/testutils"
-
 	"github.com/open-telemetry/opentelemetry-service/internal/zpagesserver"
 )
 
@@ -103,72 +98,6 @@ func TestApplication_StartUnified(t *testing.T) {
 	<-appDone
 }
 
-func testMemBallast(t *testing.T, app *Application, ballastSizeMiB int) {
-	maxRssBytes := mibToBytes(50)
-	minVirtualBytes := mibToBytes(ballastSizeMiB)
-
-	portArg := []string{
-		healthCheckHTTPPort, // Keep it as first since its address is used later.
-		zpagesserver.ZPagesHTTPPort,
-		"metrics-port",
-		"receivers.opencensus.port",
-	}
-
-	addresses := getMultipleAvailableLocalAddresses(t, uint(len(portArg)))
-	for i, addr := range addresses {
-		_, port, err := net.SplitHostPort(addr)
-		if err != nil {
-			t.Fatalf("failed to split host and port from %q: %v", addr, err)
-		}
-		app.v.Set(portArg[i], port)
-	}
-
-	// Without exporters the collector will start and just shutdown, no error is expected.
-	app.v.Set("logging-exporter", true)
-	app.v.Set("mem-ballast-size-mib", ballastSizeMiB)
-
-	appDone := make(chan struct{})
-	go func() {
-		defer close(appDone)
-		if err := app.Start(); err != nil {
-			t.Fatalf("app.Start() got %v, want nil", err)
-		}
-	}()
-
-	<-app.readyChan
-	if !isAppAvailable(t, "http://"+addresses[0]) {
-		t.Fatalf("app didn't reach ready state")
-	}
-	stats := stats.Stat{Pid: os.Getpid()}
-	err := stats.Update()
-	if err != nil {
-		panic(err)
-	}
-
-	if stats.Vsize < minVirtualBytes {
-		t.Errorf("unexpected virtual memory size. expected: >=%d, got: %d", minVirtualBytes, stats.Vsize)
-	}
-
-	if stats.Rss > maxRssBytes {
-		t.Errorf("unexpected RSS size. expected: <%d, got: %d", maxRssBytes, stats.Rss)
-	}
-
-	close(app.stopTestChan)
-	<-appDone
-}
-
-// TestApplication_MemBallast starts a new instance of collector with different
-// mem ballast sizes and ensures that ballast consumes virtual memory but does
-// not count towards RSS mem
-func TestApplication_MemBallast(t *testing.T) {
-	cases := []int{0, 500, 1000}
-	for i := 0; i < len(cases); i++ {
-		runtime.GC()
-		app := newApp()
-		testMemBallast(t, app, cases[i])
-	}
-}
-
 // isAppAvailable checks if the healthcheck server at the given endpoint is
 // returning `available`.
 func isAppAvailable(t *testing.T, healthCheckEndPoint string) bool {

go.mod

@@ -31,6 +31,7 @@ require (
 	github.com/prometheus/procfs v0.0.0-20190117184657-bf6a532e95b1
 	github.com/prometheus/prometheus v0.0.0-20190131111325-62e591f928dd
 	github.com/rs/cors v1.6.0
+	github.com/shirou/gopsutil v2.18.12+incompatible
 	github.com/soheilhy/cmux v0.1.4
 	github.com/spf13/cast v1.2.0
 	github.com/spf13/cobra v0.0.3

go.sum

@@ -302,6 +302,8 @@ github.com/sasha-s/go-deadlock v0.0.0-20161201235124-341000892f3d/go.mod h1:StQn
 github.com/satori/go.uuid v1.2.0/go.mod h1:dA0hQrYB0VpLJoorglMZABFdXlWrHn1NEOzdhQKdks0=
 github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529 h1:nn5Wsu0esKSJiIVhscUtVbo7ada43DJhG55ua/hjS5I=
 github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529/go.mod h1:DxrIzT+xaE7yg65j358z/aeFdxmN0P9QXhEzd20vsDc=
+github.com/shirou/gopsutil v2.18.12+incompatible h1:1eaJvGomDnH74/5cF4CTmTbLHAriGFsTZppLXDX93OM=
+github.com/shirou/gopsutil v2.18.12+incompatible/go.mod h1:5b4v6he4MtMOwMlS0TUMTu2PcXUg8+E1lC7eC3UO/RA=
 github.com/shopspring/decimal v0.0.0-20180709203117-cd690d0c9e24/go.mod h1:M+9NzErvs504Cn4c5DxATwIqPbtswREoFCre64PpcG4=
 github.com/shurcooL/httpfs v0.0.0-20171119174359-809beceb2371/go.mod h1:ZY1cvUeJuFPAdZ/B6v7RHavJWZn2YPVFQ1OSXhCGOkg=
 github.com/shurcooL/vfsgen v0.0.0-20180711163814-62bca832be04/go.mod h1:TrYk7fJVaAttu97ZZKrO9UbRa8izdowaMIZcxYMbVaw=