#!/usr/bin/env ruby

iter = 100
files = []
options = ""
if ARGV.length==0
  puts "usage: perf_times file1 file2 ..."
  exit 1
end
ARGV.each do |arg|
  if /^(\d+)$/===arg
    iter = $1.to_i
    next
  end
  fn = arg
  fn = fn.sub(/^\/([cdefgh])(\/)/, '\1:\2') if RUBY_PLATFORM =~ /win32/
  begin
    if File.stat(fn).readable?
      files << File.open(fn)
    else
      print "file #{fn} is unreadable\n"
      exit 1
    end
  rescue 
    print "file #{fn} does not exist\n"
    exit 1
  end
end

def truncate(text, length = 32, truncate_string = "...")
  if text.nil? then return "" end
  l = truncate_string.length + 1

  if $KCODE == "NONE"
    text.length > length ? text[0..(length - l)] + truncate_string : text
  else
    chars = text.split(//)
    chars.length > length ? chars[0..(length - l)].join + truncate_string : text
  end
end

def sum_a(a)
  a.inject(0.0){|r,v| r += v }
end
  
def time_avg(a)
  sum_a(a)/a.length
end
  
def time_dev(a, mean)
  r = a.inject(0.0){|r,v| r += (v-mean)*(v-mean) }
  Math.sqrt(r/(a.length-1))
end

files.each do |file|
  timings = {}
  keys = []
  gc_stats = []
  file.each_line do |l|
    case l
    when /^(.*)\s+([\d\.]+)\s+([\d\.]+)\s+([\d\.]+)\s+\(\s*([\d\.]+)\s*\)$/
      k = $1.strip
      keys << k
      if timings[k]
        timings[k] << $5.to_f
      else
        timings[k] = [$5.to_f]
      end
    when /^.*perf_([a-zA-Z.]+)\s+(\d+)\s+(.*)$/
      iter = $2.to_i
      options = $3
    when /^GC.collections=(\d+), GC.time=([\d\.]+)$/
      gc_stats << [$1.to_i,$2.to_f]
    end
  end

  keys.uniq!
  printf "\nperf data file: #{file.path}\n"
  printf "    requests=#{iter}, options=#{options}\n\n"
  k = 'loading environment'
  printf "%-32s  %9.5f\n\n", k, time_avg(timings[k])
  printf "%-32s  %9s  %7s  %6s  %6s\n", 'page request', 'total', 'stddev%', 'r/s', 'ms/r'

  perf_runs = timings.delete(k).length
  keys.delete(k)
  
  total_requests_run = 0
  keys.each do |k|
    t = time_avg(timings[k])
    d = time_dev(timings[k], t)
    urls = 1
    urls = $1.to_i if /\((\d+) urls\)$/===k
    total_requests_run += iter*urls
    printf "%-32s  %9.5f  %7.4f  %6.2f  %6.2f\n",
           truncate(k), t, (d/t)*100, (iter*urls)/t, t*1000/(iter*urls)
  end

  totals_per_run = (0...perf_runs).map{|i| sum_a(timings.values.map{|a| a[i]})}
  total_time = time_avg(totals_per_run)
  total_stddev = time_dev(totals_per_run, total_time)
  
  printf "\n%-32s  %9.5f  %7.4f  %6.2f  %6.2f\n",
           "all requests", total_time, (total_stddev/total_time)*100,
                        total_requests_run/total_time, total_time*1000/total_requests_run

  if gc_stats.length>0
    collection_counts = gc_stats.map{|p| p[0]}
    collection_times = gc_stats.map{|p| p[1]}
    c = time_avg(collection_counts)
    t = time_avg(collection_times)
    d = time_dev(collection_times, t)
    stddevp = t==0 ? 0 : (d/t)*100
    printf "\n%-32s  %9s  %7s  %6s  %6s\n",
           "garbage collection statistics", "time", "stddev%", "count", "total%"
    printf "%-32s  %9.5f  %7.4f  %6.2f  %6.2f\n",
           "", t, stddevp, c, (t/total_time)*100
  end

  file.close

end

__END__

### Local Variables: ***
### mode:ruby ***
### End: ***

#    Copyright (C) 2005, 2006  Stefan Kaes
#
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA