title: Garbage collector tuning in Ruby 1.9
body: <p>I know about <code>GC.enable/disable</code>, but is there any way of controlling the Ruby <strong>1.9</strong> garbage collector in more detail? </p>
  
  <p>When profiling my code (using perftools.rb) I notice that the GC stands for up to 30% of the total samples, and I'd like to see if it's possible to tune the GC to decrease this number. Are there any environment variables or other means by which you can set the number of heap slots, the malloc limit, etc. like you can with REE?</p>