Benchmark and Regression Suite for Clojure
Clojure Scala Shell


Benchmark (and regression) suite for Clojure Copyright (c) Rich Hickey.

License and CA same as Clojure. See epl-v10.html at the root of the project for details.

Getting Started


Add the following to your ~/.m2/settings.xml file


            <activation> <activeByDefault>false</activeByDefault> </activation>


git clone
cd test.benchmark
mvn test


# starts a swank server
mvn clojure:swank

Running a benchmark (e.g. alioth.thread-ring)

script/run alioth.thread-ring 1000

Timing a benchmark (e.g. alioth.fasta-redux)

time script/run alioth.fasta-redux 25000000 > /dev/null

real    0m2.389s
user    0m3.329s
sys 0m0.115s

In these results, alioth uses a measurement similar to the real timing.

Running a baseline test

Baseline tests execute a java-equivalent benchmark and compare execution times to the respective clojure benchmarks. The specifications for the baseline tests are in

# this will pull down the non-CA repo into src/baseline and build
# Currently some Java programs require JDK 1.7 for Fork/Join library.
mvn compile -Pbaseline

# afterwards you can execute baseline tests as follows

# default, run all baseline tests 3x, sample and report
script/run baseline.exec

# run all baseline tests 10x, sample and report
script/run baseline.exec 10

# run mandelbrot and thread-ring baseline tests once and report
script/run baseline.exec 1 mandelbrot thread-ring
({:failures :none,
  :id "mandelbrot",
  :metrics {:runtime {:baseline 9451.773698, :target 10316.261803}},
  :tollerances {:runtime 0.25},
  :sample-size 1}
 {:failures :none,
  :id "thread-ring",
  :metrics {:runtime {:baseline 4308.804918, :target 309.521524}},
  :tollerances {:runtime -9.0},
  :sample-size 1})

TODO: hook baseline test execution into maven test cycle and generate a jenkins-consumable report


There are a number of completed benchmarks, but there is a lot more left to do. Andy Fingerhut has a suit of benchmarks tailored for Clojure 1.2 and need updated or redone for Clojure 1.3 (

A good general approach is to examine the fastest alioth implementations, usually Java or C, and write a Clojure port. Fast small programs in any language are also worthy of examination. These benchmarks should demonstrate how to write idiomatic high-performance Clojure.

Long term goal is a performance regression test suit ...

Alioth Benchmark site is here:

Work on the benchmarks is tracked here: