snapshot of https://github.com/nats-io/nats-server.git (main, 2026-09-15; blobs > 131072B omitted)

server/pse/pse_test.go

@@ -0,0 +1,91 @@
+// Copyright 2015-2025 The NATS Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pse
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"runtime"
+	"runtime/debug"
+	"testing"
+)
+
+func TestPSEmulationCPU(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skipf("Skipping this test on Windows")
+	}
+	var rss, vss int64
+	var pcpu, psPcpu float64
+
+	debug.FreeOSMemory()
+
+	// PS version first
+	pidStr := fmt.Sprintf("%d", os.Getpid())
+	out, err := exec.Command("ps", "o", "pcpu=", "-p", pidStr).Output()
+	if err != nil {
+		t.Fatalf("Failed to execute ps command: %v\n", err)
+	}
+
+	// Our internal version
+	ProcUsage(&pcpu, &rss, &vss)
+
+	fmt.Sscanf(string(out), "%f", &psPcpu)
+
+	if pcpu != psPcpu {
+		delta := int64(pcpu - psPcpu)
+		if delta < 0 {
+			delta = -delta
+		}
+		if delta > 30 { // 30%?
+			t.Fatalf("CPUs did not match close enough: %f vs %f", pcpu, psPcpu)
+		}
+	}
+}
+
+func TestPSEmulationMem(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skipf("Skipping this test on Windows")
+	}
+	var rss, vss, psRss, psVss int64
+	var pcpu float64
+
+	debug.FreeOSMemory()
+
+	// PS version first
+	pidStr := fmt.Sprintf("%d", os.Getpid())
+	out, err := exec.Command("ps", "o", "rss=,vsz=", "-p", pidStr).Output()
+	if err != nil {
+		t.Fatalf("Failed to execute ps command: %v\n", err)
+	}
+
+	fmt.Sscanf(string(out), "%d %d", &psRss, &psVss)
+	psRss *= 1024 // 1k blocks, want bytes.
+	psVss *= 1024 // 1k blocks, want bytes.
+
+	debug.FreeOSMemory()
+
+	// Our internal version
+	ProcUsage(&pcpu, &rss, &vss)
+
+	if rss != psRss {
+		delta := rss - psRss
+		if delta < 0 {
+			delta = -delta
+		}
+		if delta > 1024*1024 { // 1MB
+			t.Fatalf("RSSs did not match close enough: %d vs %d", rss, psRss)
+		}
+	}
+}