feat: add cumulativeCPUUsage to AppMetrics and CPUUsage

This allows apps to measure their CPU usage over any given period
without worrying about other calls affecting the output,
as they would with `percentCPUUsage`.

docs/api/structures/cpu-usage.md

@@ -2,6 +2,8 @@
 
 * `percentCPUUsage` number - Percentage of CPU used since the last call to getCPUUsage.
  First call returns 0.
+* `cumulativeCPUUsage` number (optional) - Total seconds of CPU time used since process
+ startup.
 * `idleWakeupsPerSecond` number - The number of average idle CPU wakeups per second
  since the last call to getCPUUsage. First call returns 0. Will always return 0 on
  Windows.

shell/browser/api/electron_api_app.cc

@@ -1277,9 +1277,16 @@ std::vector<gin_helper::Dictionary> App::GetAppMetrics(v8::Isolate* isolate) {
  auto pid_dict = gin_helper::Dictionary::CreateEmpty(isolate);
  auto cpu_dict = gin_helper::Dictionary::CreateEmpty(isolate);
 
- std::optional<double> usage =
- process_metric.second->metrics->GetPlatformIndependentCPUUsage();
- cpu_dict.Set("percentCPUUsage", usage.value_or(0) / processor_count);
+ // Default usage percentage to 0 for compatibility
+ double usagePercent = 0;
+ if (auto usage = process_metric.second->metrics->GetCumulativeCPUUsage()) {
+ cpu_dict.Set("cumulativeCPUUsage", usage->InSecondsF());
+ usagePercent =
+ process_metric.second->metrics->GetPlatformIndependentCPUUsage(
+ *usage);
+ }
+
+ cpu_dict.Set("percentCPUUsage", usagePercent / processor_count);
 
 #if !BUILDFLAG(IS_WIN)
  cpu_dict.Set("idleWakeupsPerSecond",

shell/common/api/electron_bindings.cc

@@ -277,8 +277,15 @@ v8::Local<v8::Value> ElectronBindings::GetCPUUsage(
  v8::Isolate* isolate) {
  auto dict = gin_helper::Dictionary::CreateEmpty(isolate);
  int processor_count = base::SysInfo::NumberOfProcessors();
- std::optional<double> usage = metrics->GetPlatformIndependentCPUUsage();
- dict.Set("percentCPUUsage", usage.value_or(0) / processor_count);
+
+ // Default usage percentage to 0 for compatibility
+ double usagePercent = 0;
+ if (auto usage = metrics->GetCumulativeCPUUsage()) {
+ dict.Set("cumulativeCPUUsage", usage->InSecondsF());
+ usagePercent = metrics->GetPlatformIndependentCPUUsage(*usage);
+ }
+
+ dict.Set("percentCPUUsage", usagePercent / processor_count);
 
  // NB: This will throw NOTIMPLEMENTED() on Windows
  // For backwards compatibility, we'll return 0

spec/api-app-spec.ts

@@ -1442,6 +1442,7 @@ describe('app module', () => {
 
  types.push(entry.type);
  expect(entry.cpu).to.have.ownProperty('percentCPUUsage').that.is.a('number');
+ expect(entry.cpu).to.have.ownProperty('cumulativeCPUUsage').that.is.a('number');
  expect(entry.cpu).to.have.ownProperty('idleWakeupsPerSecond').that.is.a('number');
 
  expect(entry.memory).to.have.property('workingSetSize').that.is.greaterThan(0);

spec/api-process-spec.ts

@@ -26,6 +26,7 @@ describe('process module', () => {
  it('returns a cpu usage object', async () => {
  const cpuUsage = await w.webContents.executeJavaScript('process.getCPUUsage()');
  expect(cpuUsage.percentCPUUsage).to.be.a('number');
+ expect(cpuUsage.cumulativeCPUUsage).to.be.a('number');
  expect(cpuUsage.idleWakeupsPerSecond).to.be.a('number');
  });
  });
@@ -124,6 +125,7 @@ describe('process module', () => {
  it('returns a cpu usage object', () => {
  const cpuUsage = process.getCPUUsage();
  expect(cpuUsage.percentCPUUsage).to.be.a('number');
+ expect(cpuUsage.cumulativeCPUUsage).to.be.a('number');
  expect(cpuUsage.idleWakeupsPerSecond).to.be.a('number');
  });
  });