# File lib/new_relic/agent/vm/monotonic_gc_profiler.rb, line 22
        def total_time_s
          if NewRelic::LanguageSupport.gc_profiler_enabled?
            # There's a race here if the next two lines don't execute as an atomic
            # unit - we may end up double-counting some GC time in that scenario.
            # Locking around them guarantees atomicity of the read/increment/reset
            # sequence.
            @lock.synchronize do
              # The Ruby 1.9.x docs claim that GC::Profiler.total_time returns
              # a value in milliseconds. They are incorrect - both 1.9.x and 2.x
              # return values in seconds.
              @total_time_s += ::GC::Profiler.total_time
              ::GC::Profiler.clear
            end
          else
            NewRelic::Agent.logger.log_once(:warn, :gc_profiler_disabled,
              "Tried to measure GC time, but GC::Profiler was not enabled.")
          end

          @total_time_s
        end