class Hitimes::TimedMetric
A TimedMetric holds the metrics on how long it takes to do something. For example, measuring how long a method takes to operate.
tm = TimedMetric.new( 'my-method' ) 200.times do my_method_result = tm.measure do my_method( ... ) end end puts "#{ tm.name } operated at a rate of #{ tm.rate } calls per second"
Since TimedMetric is a child class of Metric make sure to look at the Metric API also.
A TimedMetric measures the execution time of an option with the Interval class.
A TimedMetric contains a Stats object, therefore TimedMetric has count
,
max
, mean
, min
, rate
,
stddev
, sum
, sumsq
methods that
delegate to that Stats object for convenience.
Attributes
holds all the statistics
Public Class Methods
Create a new TimedMetric giving it a name
and additional data. additional_data
may be anything that
follows the to_hash
protocol
# File lib/hitimes/timed_metric.rb, line 59 def initialize( name, additional_data = {} ) super( name, additional_data ) @stats = Stats.new @current_interval = Interval.new end
Return a TimedMetric that has been started
# File lib/hitimes/timed_metric.rb, line 44 def now( name, additional_data = {} ) t = TimedMetric.new( name, additional_data ) t.start return t end
Public Instance Methods
Measure the execution of a block and add those stats to the running stats. The return value is the return value of the block
# File lib/hitimes/timed_metric.rb, line 121 def measure( &block ) return_value = nil begin start return_value = yield ensure stop end return return_value end
return whether or not the timer is currently running.
# File lib/hitimes/timed_metric.rb, line 71 def running? @current_interval.running? end
Split the current TimedMetric. Essentially, mark a split time. This means stop the current interval and create a new interval, but make sure that the new interval lines up exactly, timewise, behind the previous interval.
If the timer is running, then split returns the duration of the previous interval, i.e. the split-time. If the timer is not running, nothing happens and false is returned.
# File lib/hitimes/timed_metric.rb, line 145 def split if @current_interval.running? then next_interval = @current_interval.split d = @current_interval.duration @stats.update( d ) @current_interval = next_interval return d end return false end
Start the current metric, if the current metric is already started, then this is a noop.
# File lib/hitimes/timed_metric.rb, line 82 def start if not @current_interval.running? then @current_interval.start @sampling_start_time ||= self.utc_microseconds() @sampling_start_interval ||= Interval.now end nil end
Stop the current metric. This updates the stats and removes the current interval. If the timer was stopped then the duration of the last Interval is returned. If the timer was already stopped then false is returned and no stats are updated.
# File lib/hitimes/timed_metric.rb, line 100 def stop if @current_interval.running? then d = @current_interval.stop @stats.update( d ) @current_interval = Interval.new # update the length of time we have been sampling @sampling_delta = @sampling_start_interval.duration_so_far return d end return false end
Convert the metric to a hash
# File lib/hitimes/timed_metric.rb, line 162 def to_hash h = super Stats::STATS.each do |s| h[s] = self.send( s ) end return h end