Added fast path for single memory ReadableBuffer (aspnet#1512)

* Special case single buffer * Added fast path for single span buffers in UvWriteReq
MaherJendoubi · Mar 20, 2017 · 39819d6 · 39819d6
1 parent 2ed456f
commit 39819d6
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Showing 2 changed files with 42 additions and 14 deletions.
diff --git a/src/Microsoft.AspNetCore.Server.Kestrel/Adapter/Internal/StreamSocketOutput.cs b/src/Microsoft.AspNetCore.Server.Kestrel/Adapter/Internal/StreamSocketOutput.cs
@@ -109,11 +109,19 @@ public async Task WriteOutputAsync()
                             await _outputStream.FlushAsync();
                         }
 
-                        foreach (var memory in buffer)
+                        if (buffer.IsSingleSpan)
                         {
-                            var array = memory.GetArray();
+                            var array = buffer.First.GetArray();
                             await _outputStream.WriteAsync(array.Array, array.Offset, array.Count);
                         }
+                        else
+                        {
+                            foreach (var memory in buffer)
+                            {
+                                var array = memory.GetArray();
+                                await _outputStream.WriteAsync(array.Array, array.Offset, array.Count);
+                            }
+                        }
                     }
                     finally
                     {

diff --git a/src/Microsoft.AspNetCore.Server.Kestrel/Internal/Networking/UvWriteReq.cs b/src/Microsoft.AspNetCore.Server.Kestrel/Internal/Networking/UvWriteReq.cs
@@ -4,7 +4,6 @@
 using System;
 using System.Buffers;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.IO.Pipelines;
 using System.Runtime.InteropServices;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
@@ -68,9 +67,16 @@ private unsafe void Write(
                 _pins.Add(GCHandle.Alloc(this, GCHandleType.Normal));
 
                 var nBuffers = 0;
-                foreach (var _ in buffer)
+                if (buffer.IsSingleSpan)
                 {
-                    nBuffers++;
+                    nBuffers = 1;
+                }
+                else
+                {
+                    foreach (var _ in buffer)
+                    {
+                        nBuffers++;
+                    }
                 }
 
                 var pBuffers = (Libuv.uv_buf_t*)_bufs;
@@ -82,19 +88,33 @@ private unsafe void Write(
                     _pins.Add(gcHandle);
                     pBuffers = (Libuv.uv_buf_t*)gcHandle.AddrOfPinnedObject();
                 }
-                var index = 0;
-                foreach (var memory in buffer)
+
+                if (nBuffers == 1)
                 {
-                    // REVIEW: This isn't necessary for our default pool since the memory is 
-                    // already pinned but it also makes tests pass
+                    var memory = buffer.First;
                     var memoryHandle = memory.Pin();
                     _handles.Add(memoryHandle);
 
-                    // create and pin each segment being written
-                    pBuffers[index] = Libuv.buf_init(
-                        (IntPtr)memoryHandle.PinnedPointer,
-                        memory.Length);
-                    index++;
+                    // Fast path for single buffer
+                    pBuffers[0] = Libuv.buf_init(
+                            (IntPtr)memoryHandle.PinnedPointer,
+                            memory.Length);
+                }
+                else
+                {
+                    var index = 0;
+                    foreach (var memory in buffer)
+                    {
+                        // This won't actually pin the buffer since we're already using pinned memory
+                        var memoryHandle = memory.Pin();
+                        _handles.Add(memoryHandle);
+
+                        // create and pin each segment being written
+                        pBuffers[index] = Libuv.buf_init(
+                            (IntPtr)memoryHandle.PinnedPointer,
+                            memory.Length);
+                        index++;
+                    }
                 }
 
                 _callback = callback;