stat-collector.tcl

# Author : Hari Balakrishnan
# Class that encapsulates all statistics collection.

Class StatCollector 

StatCollector instproc init {id ctype} {
    $self set srcid_ $id
    $self set ctype_ $ctype;    # type of congestion control / tcp
    $self set numbytes_ 0
    $self set ontime_ 0.0;     # total time connection was in ON state
    $self set cumrtt_ 0.0
    $self set rtt_samples_ {}
    $self set nsamples_ 0
    $self set nconns_ 0
}

StatCollector instproc showstats {final id} {
  global opt
  set res [$self results]
  set totalbytes [lindex $res 0]
  set totaltime [lindex $res 1]
  set totalrtt [lindex $res 2]
  set nsamples [lindex $res 3]
  set nconns [lindex $res 4]
  set all_rtt_samples [lindex $res 5]

  if { $nsamples > 0.0 } {
      set avgrtt [expr 1000*$totalrtt/$nsamples]
  } else {
      set avgrtt 0.0
  }
  set reqd_index [expr round (floor ($nsamples * 0.95)) ]
  set sorted [lsort $all_rtt_samples]
  set rtt95th [expr [lindex $sorted $reqd_index] * 1000]

  if { $totaltime > 0.0 } {
      set throughput [expr 8.0 * $totalbytes / $totaltime]
      set utility [expr log($throughput) - [expr log($rtt95th)]]
      if { $final == True } {
          puts [ format "FINAL id %d bytes %d mbps %.3f avgrtt %.1f rtt-95th %.1f on_percentage %.4f utility %.2f num_connections %d nsamples %d" $id $totalbytes [expr $throughput/1000000.0] $avgrtt $rtt95th [expr 100.0*$totaltime/$opt(duration)] $utility $nconns $nsamples ]
      } else {
          puts [ format "----- id %d bytes %d mbps %.3f avgrtt %.1f rtt-95th %.1f on_percentage %.4f utility %.2f num_connections %d nsamples %d" $id $totalbytes [expr $throughput/1000000.0] $avgrtt $rtt95th [expr 100.0*$totaltime/$opt(duration)] $utility $nconns $nsamples ]
      }
  }
}

StatCollector instproc update {newbytes newtime cumrtt nsamples rtt_samples} {
    global ns opt
    $self instvar srcid_ numbytes_ ontime_ cumrtt_ nsamples_ nconns_ rtt_samples_
    incr numbytes_ $newbytes
    set ontime_ [expr $ontime_ + $newtime]
    set cumrtt_ [expr $cumrtt_ + $cumrtt]
    incr nsamples_ $nsamples
    set rtt_samples_ $rtt_samples
    incr nconns_
    if {$opt(verbose)} {
        puts [format "%.2f: updating stats $srcid_: $newbytes %.2f %.3f $nsamples" [$ns now] $newtime $cumrtt]
        puts [format "%.2f: Total so far: $numbytes_ %.2f %.3f $nsamples_" [$ns now] $ontime_ $cumrtt_]
    }
    if { $opt(partialresults) } {
        $self showstats False
    }
}

StatCollector instproc results { } {
    $self instvar numbytes_ ontime_ cumrtt_ nsamples_ nconns_ rtt_samples_
    return [list $numbytes_ $ontime_ $cumrtt_ $nsamples_ $nconns_ $rtt_samples_]
}