master consumes large amount of CPU for days

[Ted Tuttle]

Hello-

Our master process started consuming a large amount of CPU (75% of box) several 
days back and hasn't stopped.  I have 2 questions:

                1) what is it doing (stack dump and log below)
                2) is it safe to restart the master without taking the whole 
cluster down?

Master stack dump:

                http://pastebin.com/G0iNNEpC

Master log from last 15 mins or so:

                http://pastebin.com/WQNjhFGf

Thanks,
Ted