diff --git a/spec/ruby/core/process/clock_getres_spec.rb b/spec/ruby/core/process/clock_getres_spec.rb
index dc78fc4c88..5e5eb0246c 100644
--- a/spec/ruby/core/process/clock_getres_spec.rb
+++ b/spec/ruby/core/process/clock_getres_spec.rb
@@ -11,20 +11,24 @@ describe "Process.clock_getres" do
         end
         reported = Process.clock_getres(value, :nanosecond)
 
-        # The clock should not be more accurate than reported (times should be
-        # a multiple of reported precision.)
-        times.select { |t| t % reported > 0 }.should be_empty
+        # CentOS seems to report a negative resolution:
+        # https://rubyci.org/logs/rubyci.s3.amazonaws.com/centos6/ruby-trunk/log/20190428T093004Z.fail.html.gz
+        unless name == :CLOCK_MONOTONIC_RAW and reported < 0
+          # The clock should not be more accurate than reported (times should be
+          # a multiple of reported precision.)
+          times.select { |t| t % reported > 0 }.should be_empty
 
-        # We're assuming precision is a multiple of ten - it may or may not
-        # be an incompatibility if it isn't but we'd like to notice this,
-        # and the spec following these wouldn't work if it isn't.
-        reported.should > 0
-        (reported == 1 || reported % 10 == 0).should be_true
+          # We're assuming precision is a multiple of ten - it may or may not
+          # be an incompatibility if it isn't but we'd like to notice this,
+          # and the spec following these wouldn't work if it isn't.
+          reported.should > 0
+          (reported == 1 || reported % 10 == 0).should be_true
 
-        # The clock should not be less accurate than reported (times should
-        # not all be a multiple of the next precision up, assuming precisions
-        # are multiples of ten.)
-        times.select { |t| t % (reported * 10) == 0  }.size.should_not == times.size
+          # The clock should not be less accurate than reported (times should
+          # not all be a multiple of the next precision up, assuming precisions
+          # are multiples of ten.)
+          times.select { |t| t % (reported * 10) == 0  }.size.should_not == times.size
+        end
       end
     end
   end