JMeter with Graphite
JMeter, probably the most popular open-source tool for load testing, can now report test results to Graphite! The Graphite listener is not part of the latest release (2.12), but it is included in the nightly build and it works quite well. It can report summary statistics for the entire test run or statistics for specific samplers with successes and failure counts, percentiles and so on. Highly recommended, in particular if the system under test also reports statistics to Graphite!