First pass at benchmarking for C#

benchmarks/README.md

@@ -65,6 +65,12 @@ include PHP protobuf's src and build the c extension if required.
 ### Node.js
 Node.js benchmark need [node](https://nodejs.org/en/)(higher than V6) and [npm](https://www.npmjs.com/) package manager installed. This benchmark is using the [benchmark](https://www.npmjs.com/package/benchmark) framework to test, which needn't to manually install. And another prerequisite is [protobuf js](https://github.com/protocolbuffers/protobuf/tree/master/js), which needn't to manually install either
 
+### C#
+The C# benchmark code is built as part of the main Google.Protobuf
+solution. It requires the .NET Core SDK, and depends on
+[BenchmarkDotNet](https://github.com/dotnet/BenchmarkDotNet), which
+will be downloaded automatically.
+
 ### Big data
 
 There's some optional big testing data which is not included in the directory
@@ -74,7 +80,7 @@ initially, you need to run the following command to download the testing data:
 $ ./download_data.sh
 ```
 
-After doing this the big data file will automaticly generated in the
+After doing this the big data file will automatically generated in the
 benchmark directory.
 
 ## Run instructions
@@ -209,6 +215,15 @@ $ make js-benchmark
 $ ./js-benchmark $(specific generated dataset file name)
 ```
 
+### C#
+From `csharp/src/Google.Protobuf.Benchmarks`, run:
+
+```
+$ dotnet run -c Release
+```
+
+We intend to add support for this within the makefile in due course.
+
 ## Benchmark datasets
 
 Each data set is in the format of benchmarks.proto:

csharp/.gitignore

@@ -29,3 +29,6 @@ mono/*.exe
 mono/*.dll
 lib/protoc.exe
 *.ncrunch*
+
+# Benchmark output
+BenchmarkDotNet.Artifacts/

csharp/generate_protos.sh

@@ -61,3 +61,9 @@ $PROTOC -Iexamples -Isrc --csharp_out=csharp/src/AddressBook \
 
 $PROTOC -Iconformance -Isrc --csharp_out=csharp/src/Google.Protobuf.Conformance \
     conformance/conformance.proto
+
+# Benchmark protos
+$PROTOC -Ibenchmarks \
+  benchmarks/datasets/google_message1/proto3/*.proto \
+  benchmarks/benchmarks.proto \
+  --csharp_out=csharp/src/Google.Protobuf.Benchmarks