From Mexico.purplecow.org

System call breakdown for ruby's "gem" command

Called with no parameters - the sole actual work is to print usage information. It takes a long time, so let's have a look at what happens:

$ truss gem >rubygem.truss 2>&1
$ grep -c open rubygem.truss
656
$ grep -c stat rubygem.truss
1372
$ wc -l rubygem.truss
    4836 rubygem.truss

Oh dear! So what is it actually doing?