Update according to first review

src/benchmarks/micro/corefx/System.Threading.Tasks.Dataflow/Perf.ActionBlock.cs

@@ -21,19 +21,6 @@ public override ActionBlock<int> CreateBlock() =>
             );
     }
 
-    public class UnorderedParallelActionBlockPerfTests : TargetPerfTests<ITargetBlock<int>>
-    {
-        public override ITargetBlock<int> CreateBlock() =>
-            new ActionBlock<int>(
-                i => { },
-                new ExecutionDataflowBlockOptions
-                {
-                    MaxDegreeOfParallelism = Environment.ProcessorCount,
-                    EnsureOrdered = false
-                }
-            );
-    }
-
     public class SingleProducerConstrainedActionBlockPerfTests : TargetPerfTests<ITargetBlock<int>>
     {
         public override ITargetBlock<int> CreateBlock() =>

src/benchmarks/micro/corefx/System.Threading.Tasks.Dataflow/Perf.BroadcastBlock.cs

@@ -10,13 +10,7 @@ namespace System.Threading.Tasks.Dataflow.Tests
     [BenchmarkCategory(Categories.CoreFX)]
     public class BroadcastBlockPerfTests : ReceivablePropagatorPerfTests<BroadcastBlock<int>, int>
     {
-        public override BroadcastBlock<int> CreateBlock() =>
-            new BroadcastBlock<int>(
-                i => i,
-                new ExecutionDataflowBlockOptions
-                {
-                    MaxDegreeOfParallelism = Environment.ProcessorCount
-                });
+        public override BroadcastBlock<int> CreateBlock() => new BroadcastBlock<int>(i => i);
 
         [Benchmark(OperationsPerInvoke = MessagesCount)]
         public Task PostMultiReceiveParallel() => MultiParallel(() => Post());

src/benchmarks/micro/corefx/System.Threading.Tasks.Dataflow/Perf.Dataflow.cs

@@ -16,7 +16,7 @@ public abstract class PerfTests<T> where T : IDataflowBlock
 
         public abstract T CreateBlock();
 
-        [GlobalSetup]
+        [IterationSetup]
         public void BlockSetup()
         {
             block = CreateBlock();