add wrk2

- signed-off-by: trimstray <trimstray@gmail.com>

README.md

@@ -178,6 +178,7 @@ Only main chapters:
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://httpd.apache.org/docs/2.4/programs/ab.html"><b>ab</b></a> - is a single-threaded command line tool for measuring the performance of HTTP web servers.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://www.joedog.org/siege-home/"><b>siege</b></a> - is an http load testing and benchmarking utility.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/wg/wrk"><b>wrk</b></a> - is a modern HTTP benchmarking tool capable of generating significant load.<br>
+&nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/giltene/wrk2"><b>wrk2</b></a> - is a constant throughput, correct latency recording variant of wrk.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/codesenberg/bombardier"><b>bombardier</b></a> - is a fast cross-platform HTTP benchmarking tool written in Go.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/cmpxchg16/gobench"><b>gobench</b></a> - http/https load testing and benchmarking tool.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/rakyll/hey"><b>hey</b></a> - HTTP load generator, ApacheBench (ab) replacement, formerly known as rakyll/boom.<br>