From: Bill Kelly <billk@...>
Date: 2007-11-15T03:32:11+09:00
Subject: Re: ruby incredibly slow (update 2)


From: "Ron Jeffries" <ronjeffries@acm.org>
>
> When in the Rails ruby folder, we run
>  ruby runner.rb ruby
> Chet's machine takes about 6 seconds, and mine takes 93 seconds.

This may be like 'slaking a thirst with a firehose', but...

Maybe instrumenting runner.rb with a trace function:

def __trace_on__
  trace_proc = proc do |event, file, line, id, binding, classname|
    return if file =~ %r{lib/ruby/}
    trace_str = sprintf( "%14.3f %8s %s:%-2d %10s %8s <%d>",
                         Time.now.to_f, event, file, line, id,
                         classname, Thread.current.object_id )
    $stderr.puts trace_str
  end
  set_trace_func trace_proc
end

def __trace_off__
  set_trace_func nil
end

__trace_on__


... This will output a LOT of information, tracing each line
of code executed and printing a timestamp.  But maybe it might
reveal something about where the slowdown is occurring.  (If
the tracing itself doesn't add so much overhead as to mask
the problem <grin>.)

Note that by default, to cut down on the spam, I have the trace
func ignore files having lib/ruby/ in their path.  You may need
to modify that if you aren't seeing the output you're interested
in.


Hope this helps,

Bill