Add getuid benchmark

git-svn-id: http://svn.codehaus.org/jruby/trunk/jruby@7435 961051c9-f516-0410-bf72-c9f7e237a7b7

Author: vp-of-awesome

test/bench/ffi/bench_getuid.rb

@@ -0,0 +1,25 @@
+require 'benchmark'
+require 'ffi'
+
+iter = 100000
+
+module Posix
+  extend FFI::Library
+  attach_function :getuid, [], :uid_t
+end
+
+
+puts "uid=#{Process.pid} Posix.getuid=#{Posix.getuid}"
+puts "Benchmark FFI getuid performance, #{iter}x calls"
+
+10.times {
+  puts Benchmark.measure {
+    iter.times { Posix.getuid }
+  }
+}
+puts "Benchmark Process.uid performance, #{iter}x calls"
+10.times {
+  puts Benchmark.measure {
+    iter.times { Process.uid }
+  }
+}