qpc-github / gctrack

The GCTrack extension lets you monitor incremental GC information

GCTrack

The GCTrack extension lets you monitor incremental Garbage Collector (GC) information, the GC introduced in Ruby v2.2.

Getting started

#1 Add the dependency

GCTrack is published to rubygems.org. Simply add it as a dependency to your Gemfile

gem 'gctrack', '~> 0.1.1'

#2 Enable the extension

require 'gctrack'

GC::Tracker.enable # returns true, if the Tracker is now enabled

#3 Record data

GC::Tracker.start_record # returns true, if a new record was started
# DO ACTUAL WORK
gc_cycles, gc_duration_ns = GC::Tracker.end_record

#end_record will return the gc_cycles (the amount of gc cycles observed) and gc_duration_ns (their cumulative duration in nanoseconds), since the last invocation of #start_record. You can also invoke #start_record recursively as so:

GC::Tracker.start_record # Start a first record 
do_work_on(one)
GC::Tracker.start_record # Start a second record 
do_work_on(two)
inner_data = GC::Tracker.end_record # Collect results from second record
do_work_on(three)
outter_data = GC::Tracker.end_record # Collect results from first record

In this example, the Array inner_data will only contain the GC information resulted of executing do_work_on(two), while outter_data will contain the GC information resulted from the three exectutions: do_work_on one, two and three.

Effectively, records are stacked and data from a GC cycle will be added to all "currently" records.

License

The MIT License (MIT)