use monotonic clock if possible on Ruby 2.1+

The monotonic clock is immune to discontinuous time jumps while
still taking into account clock imperfections, making it appropriate
for calculating time differences and timeouts.

1 files changed, 10 insertions, 0 deletions

diff --git a/lib/mogilefs.rb b/lib/mogilefs.rb
index dd60e91..6059836 100644
--- a/lib/mogilefs.rb
+++ b/lib/mogilefs.rb
@@ -5,6 +5,16 @@
 # Client usage information is available in MogileFS::MogileFS.
 module MogileFS
 
+  if defined?(Process::CLOCK_MONOTONIC)
+    def self.now
+      Process.clock_gettime(Process::CLOCK_MONOTONIC)
+    end
+  else
+    def self.now
+      Time.now.to_f
+    end
+  end
+
   # Standard error class for most MogileFS-specific errors
   class Error < StandardError; end