tools/multigcc.pl

   1 #!/usr/bin/perl
   2 use Switch;
   3 use List::Util 'shuffle'; # standard from Perl 5.8 and later
   4
   5 my $tempfile = "multigcc.out";
   6 my @params;
   7 my @files;
   8 my $list = \@params;
   9
  10 # parse command line arguments
  11 for my $a (@ARGV) {
  12     if ($a eq "--") {
  13         $list = \@files;
  14         next;
  15     }
  16
  17     push @{$list}, $a;
  18 }
  19
  20 exit if (not @files);
  21
  22 my $command = join " ", @params;
  23
  24 # shuffle the file list to spread the load as evenly as we can
  25 @files = shuffle(@files);
  26
  27 # count number of cores
  28 my $cores;
  29 switch($^O) {
  30     case "darwin" {
  31         chomp($cores = `sysctl -n hw.ncpu`);
  32         $cores = 1 if ($?);
  33     }
  34     case "solaris" {
  35         $cores = scalar grep /on-line/i, `psrinfo`;
  36         $cores = 1 if ($?);
  37     }
  38     else {
  39         if (open CPUINFO, "</proc/cpuinfo") {
  40             $cores = scalar grep /^processor/i, <CPUINFO>;
  41             close CPUINFO;
  42         }
  43         else {
  44             $cores = 1;
  45         }
  46     }
  47 }
  48
  49 # don't run empty children
  50 if (scalar @files <= $cores)
  51 {
  52     $cores = 1;
  53 }
  54
  55 # fork children
  56 my @pids;
  57 my $slice = int((scalar @files + $cores) / $cores);
  58 for my $i (0 .. $cores-1)
  59 {
  60     my $pid = fork;
  61     if ($pid)
  62     {
  63         # mother
  64         $pids[$i] = $pid;
  65     }
  66     else
  67     {
  68         # get my slice of the files
  69         my @list = @files[$i * $slice .. $i * $slice + $slice - 1];
  70
  71         # run command
  72         system("$command @list > $tempfile.$$");
  73
  74         exit;
  75     }
  76 }
  77
  78 for my $i (0 .. $cores - 1)
  79 {
  80     # wait for child to complete
  81     waitpid $pids[$i], 0;
  82
  83     # read & print result
  84     if (open F, "<$tempfile.$pids[$i]")
  85     {
  86         print <F>;
  87         close F;
  88         unlink "$tempfile.$pids[$i]";
  89     }
  90 }