static void Main(string[] args)
{
// build a "class histogram" (i.e. !dumpheap -stat in WinDBG+sos)
// in an optimized way
using (DataTarget dt = TestTargets.Types.LoadFullDump())
{
ClrRuntime runtime = dt.ClrVersions[0].CreateRuntime();
ClrHeap heap = runtime.Heap;
var statistics = new Dictionary <ClrType, TypeEntry>(32768);
int objectCount = 0;
// build the class histogram: count and cumulated size of instances per type
foreach (var objDetails in heap.EnumerateObjectDetails())
{
ulong address = objDetails.Item1;
ulong mt = objDetails.Item2;
ClrType type = objDetails.Item3;
ulong size = objDetails.Item4;
TypeEntry entry;
if (!statistics.TryGetValue(type, out entry))
{
entry = new TypeEntry()
{
TypeName = type.Name,
MethodTable = mt,
Size = 0
};
statistics[type] = entry;
}
entry.Count++;
entry.Size += size;
objectCount++;
}
// display a la !dumpheap -stat
var sortedStatistics =
from entry in statistics.Values
orderby entry.Size
select entry;
Console.WriteLine("{0,12} {1,12} {2,12} {3}", "MT", "Count", "TotalSize", "Class Name");
foreach (var entry in sortedStatistics)
{
Console.WriteLine($"{entry.MethodTable,12:X12} {entry.Size,12:D} {entry.Count,12:D} {entry.TypeName}");
}
Console.WriteLine($"Total {objectCount} objects");
}
}
public void OptimizedClassHistogram()
{
using (DataTarget dt = TestTargets.Types.LoadFullDump())
{
ClrRuntime runtime = dt.ClrVersions.Single().CreateRuntime();
ClrHeap heap = runtime.Heap;
// ensure that the optimized version is faster than the default one
Stopwatch timing = new Stopwatch();
var notOptimizedStatistics = new Dictionary <ClrType, TypeEntry>(32768);
int notOptimizedObjectCount = 0;
// with an optimized version
timing.Start();
foreach (var objDetails in heap.EnumerateObjectDetails())
{
ClrType type = objDetails.Item3;
ulong size = objDetails.Item4;
TypeEntry entry;
if (!notOptimizedStatistics.TryGetValue(type, out entry))
{
entry = new TypeEntry()
{
TypeName = type.Name,
Size = 0
};
notOptimizedStatistics[type] = entry;
}
entry.Count++;
entry.Size += size;
notOptimizedObjectCount++;
}
timing.Stop();
var notOptimizedTime = TimeSpan.FromMilliseconds(timing.ElapsedMilliseconds);
// with an non-optimized version
var statistics = new Dictionary <ClrType, TypeEntry>(32768);
int objectCount = 0;
timing.Restart();
foreach (ulong objAddress in heap.EnumerateObjectAddresses())
{
ClrType type = heap.GetObjectType(objAddress);
ulong size = type.GetSize(objAddress);
TypeEntry entry;
if (!statistics.TryGetValue(type, out entry))
{
entry = new TypeEntry()
{
TypeName = type.Name,
Size = 0
};
statistics[type] = entry;
}
entry.Count++;
entry.Size += size;
objectCount++;
}
timing.Stop();
// check object count
Assert.AreEqual(notOptimizedObjectCount, objectCount);
// check heap content
var types = notOptimizedStatistics.Keys;
foreach (var type in types)
{
var notOptimizedDetails = notOptimizedStatistics[type];
var details = statistics[type];
Assert.AreEqual(notOptimizedDetails.TypeName, details.TypeName);
Assert.AreEqual(notOptimizedDetails.Count, details.Count);
Assert.AreEqual(notOptimizedDetails.Size, details.Size);
}
Assert.AreEqual(types.Count, statistics.Count);
// checking that optimized is faster could be flaky
// Assert.IsTrue(notOptimizedTime > TimeSpan.FromMilliseconds(timing.ElapsedMilliseconds));
}
}
