#78 - Import JMH Benchmarks readme.

benchmark/README.md

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+# Benchmarks
+
+Benchmarks are based on [JMH](http://openjdk.java.net/projects/code-tools/jmh/).
+
+# Running Benchmarks
+
+To run the benchmarks with default settings use:
+
+```bash
+mvn clean test
+```
+
+A basic report will be printed to the CLI.
+
+```bash
+# Run complete. Total time: 00:00:15
+
+Benchmark                                    Mode  Cnt        Score       Error  Units
+MappingMongoConverterBenchmark.readObject   thrpt   10  1920157,631 ± 64310,809  ops/s
+MappingMongoConverterBenchmark.writeObject  thrpt   10   782732,857 ± 53804,130  ops/s
+```
+
+## Running all Benchmarks of a specific class
+
+To run all Benchmarks of a specific class, just provide its simple class name via the `benchmark` command line argument.
+
+```bash
+mvn clean test -D benchmark=MappingMongoConverterBenchmark
+```
+
+## Running a single Benchmark
+
+To run a single Benchmark provide its containing class simple name followed by `#` and the method name via the `benchmark` command line argument.
+
+```bash
+mvn clean test -D benchmark=MappingMongoConverterBenchmark#readObjectWith2Properties
+```
+
+# Saving Benchmark Results
+
+A detailed benchmark report is stored in JSON format in the `/target/reports/performance` directory.
+To store the report in a different location use the `benchmarkReportDir` command line argument.
+
+## MongoDB
+
+Results can be directly piped to MongoDB by providing a valid [Connection String](https://docs.mongodb.com/manual/reference/connection-string/) via the `publishTo` command line argument.
+
+```bash
+mvn clean test -D publishTo=mongodb://127.0.0.1:27017
+```
+
+NOTE: If the uri does not explicitly define a database the default `spring-data-mongodb-benchmarks` is used. 
+
+## HTTP Endpoint
+
+The benchmark report can also be posted as `application/json` to an HTTP Endpoint by providing a valid URl via the `publishTo` command line argument.
+
+```bash
+mvn clean test -D publishTo=http://127.0.0.1:8080/capture-benchmarks
+```
+
+# Customizing Benchmarks
+
+Following options can be set via command line.
+
+Option | Default Value
+--- | ---
+warmupIterations | 10
+warmupTime | 1 (seconds)
+measurementIterations | 10
+measurementTime | 1 (seconds)
+forks | 1
+benchmarkReportDir | /target/reports/performance (always relative to project root dir)
+benchmark | .* (single benchmark via `classname#benchmark`)
+publishTo | \[not set\] (mongodb-uri or http-endpoint)