Add a benchmark

The benchmark tests a single heavily contended counter.

benchmarks/Benchmarks.hs

@@ -0,0 +1,24 @@
+{-# LANGUAGE BangPatterns, OverloadedStrings #-}
+
+-- | Perform 100,000 atomic increments using 100 concurrent writers.
+module Main where
+
+import Control.Concurrent
+import Control.Monad
+import System.Remote.Counter
+import System.Remote.Monitoring
+
+main :: IO ()
+main = do
+    handle <- forkServer "localhost" 8000
+    counter <- getCounter "iterations" handle
+    locks <- replicateM n newEmptyMVar
+    mapM_ (forkIO . work counter iters) locks
+    mapM_ takeMVar locks
+  where
+    n = 100
+    iters = 100000
+
+    work :: Counter -> Int -> MVar () -> IO ()
+    work !_ 0 !lock     = putMVar lock ()
+    work counter i lock = inc counter >> work counter (i - 1) lock

ekg.cabal

@@ -20,6 +20,7 @@ data-files:          assets/index.html assets/monitor.js assets/monitor.css
 extra-source-files:  LICENSE.icons LICENSE.javascript README.md
                      assets/jquery-1.6.4.js assets/jquery.flot.js
                      examples/Basic.hs CHANGES.md
+cabal-version:       >= 1.8
 
 library
   exposed-modules:
@@ -52,6 +53,17 @@ library
 
   ghc-options: -Wall
 
+benchmark benchmarks
+  hs-source-dirs: benchmarks
+  main-is: Benchmarks.hs
+  type: exitcode-stdio-1.0
+
+  build-depends:
+    base,
+    ekg
+
+  ghc-options: -O2 -threaded -Wall
+
 source-repository head
   type:     git
   location: https://github.com/tibbe/ekg.git