change GC committed bytes unit to MB (#51031)

* change GC committed bytes unit to MB

* change other memory counters to use 1_000_000

src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/RuntimeEventSource.cs

@@ -62,8 +62,8 @@ protected override void OnEventCommand(EventCommandEventArgs command)
 
  // On disable, PollingCounters will stop polling for values so it should be fine to leave them around.
  _cpuTimeCounter ??= new PollingCounter("cpu-usage", this, () => RuntimeEventSourceHelper.GetCpuUsage()) { DisplayName = "CPU Usage", DisplayUnits = "%" };
- _workingSetCounter ??= new PollingCounter("working-set", this, () => (double)(Environment.WorkingSet / 1000000)) { DisplayName = "Working Set", DisplayUnits = "MB" };
- _gcHeapSizeCounter ??= new PollingCounter("gc-heap-size", this, () => (double)(GC.GetTotalMemory(false) / 1000000)) { DisplayName = "GC Heap Size", DisplayUnits = "MB" };
+ _workingSetCounter ??= new PollingCounter("working-set", this, () => (double)(Environment.WorkingSet / 1_000_000)) { DisplayName = "Working Set", DisplayUnits = "MB" };
+ _gcHeapSizeCounter ??= new PollingCounter("gc-heap-size", this, () => (double)(GC.GetTotalMemory(false) / 1_000_000)) { DisplayName = "GC Heap Size", DisplayUnits = "MB" };
  _gen0GCCounter ??= new IncrementingPollingCounter("gen-0-gc-count", this, () => GC.CollectionCount(0)) { DisplayName = "Gen 0 GC Count", DisplayRateTimeScale = new TimeSpan(0, 1, 0) };
  _gen1GCCounter ??= new IncrementingPollingCounter("gen-1-gc-count", this, () => GC.CollectionCount(1)) { DisplayName = "Gen 1 GC Count", DisplayRateTimeScale = new TimeSpan(0, 1, 0) };
  _gen2GCCounter ??= new IncrementingPollingCounter("gen-2-gc-count", this, () => GC.CollectionCount(2)) { DisplayName = "Gen 2 GC Count", DisplayRateTimeScale = new TimeSpan(0, 1, 0) };
@@ -77,7 +77,7 @@ protected override void OnEventCommand(EventCommandEventArgs command)
  var gcInfo = GC.GetGCMemoryInfo();
  return gcInfo.HeapSizeBytes != 0 ? gcInfo.FragmentedBytes * 100d / gcInfo.HeapSizeBytes : 0;
  }) { DisplayName = "GC Fragmentation", DisplayUnits = "%" };
- _committedCounter ??= new PollingCounter("gc-committed", this, () => GC.GetGCMemoryInfo().TotalCommittedBytes) { DisplayName = "GC Committed Bytes", DisplayUnits = "B" };
+ _committedCounter ??= new PollingCounter("gc-committed", this, () => (double)(GC.GetGCMemoryInfo().TotalCommittedBytes / 1_000_000)) { DisplayName = "GC Committed Bytes", DisplayUnits = "MB" };
 #if !MONO
  _exceptionCounter ??= new IncrementingPollingCounter("exception-count", this, () => Exception.GetExceptionCount()) { DisplayName = "Exception Count", DisplayRateTimeScale = new TimeSpan(0, 0, 1) };
  _gcTimeCounter ??= new PollingCounter("time-in-gc", this, () => GC.GetLastGCPercentTimeInGC()) { DisplayName = "% Time in GC since last GC", DisplayUnits = "%" };