Add Http client bench marks with S3 Get/Put

Author: joviegas

pom.xml

@@ -79,6 +79,7 @@
         <module>test/test-utils</module>
         <module>test/codegen-generated-classes-test</module>
         <module>test/sdk-benchmarks</module>
+        <module>test/http-client-benchmarks</module>
         <module>test/module-path-tests</module>
         <module>test/tests-coverage-reporting</module>
         <module>test/stability-tests</module>

test/http-client-benchmarks/README.md

@@ -0,0 +1,38 @@
+# Sdk Benchmark Harness
+
+
+This module contains sdk benchmark harness using [JMH].
+
+Each benchmark class has a set of default
+JMH configurations tailored to SDK's build job and you might need to
+adjust them based on your test environment such as increasing warmup iterations
+or measurement time in order to get more reliable data.
+
+There are three ways to run benchmarks.
+
+- Using the executable JAR (Preferred usage per JMH site)
+```bash
+mvn clean install -P quick -pl :sdk-benchmarks --am
+
+# Run specific benchmark
+java -jar target/benchmarks.jar ApacheHttpClientBenchmark
+
+# Run all benchmarks: 3 warm up iterations, 3 benchmark iterations, 1 fork
+java -jar target/benchmarks.jar -wi 3 -i 3 -f 1
+```
+
+- Using`mvn exec:exec` commands to invoke `UnifiedBenchmarkRunner` main method
+```bash
+   mvn clean install -P quick -pl :sdk-benchmarks --am
+   mvn clean install -pl :bom-internal
+   cd test/sdk-benchmarks
+   mvn exec:exec
+```   
+
+- From IDE
+  
+  You can run the main method within each Benchmark class from your IDE. If you are using Eclipse, you might need to
+  set up build configurations for JMH annotation, please check [JMH]. Note that the benchmark result from IDE 
+  might not be as reliable as the above approaches and is generally not recommended.
+  
+[JMH]: http://openjdk.java.net/projects/code-tools/jmh/