DATAMONGO-1720 - Add JMH based benchmark module

[christophstrobl]

⚠️ commits 67376b8 & 05a3cc7 need to be dropped when merging ⚠️

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Running Benchmarks

Running benchmarks is disabled by default and can be activated via the benchmarks profile.
To run the benchmarks with default settings use.

mvn -P benchmarks clean test

A basic report will be printed to the CLI.

# 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.

mvn -P benchmarks 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.

mvn -P benchmarks 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 via the publishTo command line argument.

mvn -P benchmarks clean test -D publishTo=mongodb://127.0.0.1:27017

ℹ️ 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.

mvn -P benchmarks 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)

[odrotbohm]

Superfluous "t".

[christophstrobl]

backported recent changes to spring-projects/spring-data-mongodb/issue/1.10.x/DATAMONGO-1720 brach.