lib/cpu/usage_sampler.rb in cpu-0.0.0 vs lib/cpu/usage_sampler.rb in cpu-0.0.1

@@ -1,20 +1,29 @@
 module CPU
   class UsageSampler
+    # Creates a new UsageSampler instance.
     def initialize
       sample
     end
 
+    # Return all CPU::Usage instances stored in this UsageSampler, if any.
     attr_reader :usages
 
+    # Returns a CPU::Usage instance, that sums up all CPU::Usage instances for
+    # all processors in this computer.
     def sum_usages
       @usages and @usages.values.inject(&:+)
     end
 
+    # This regular expression is used to parse cpu times from the /proc/stat
+    # kernel file.
     CPU = /^cpu(\d+)#{'\s+(\d+)' * 4}/
 
+    # This value is used to convert cpu times from jiffies into seconds.
     USER_HZ = 100
 
+    # Take one sample of CPU usage data for every processor in this computer
+    # and store them in the +usages+ attribute.
     def sample
       total, @usages = nil, {}
       timestamp = Time.now
       File.foreach('/proc/stat') do |line|
         case line