Memtest Runs Periodically

Ubuntu 14.04

Hi.

My system has recently begun ruing some sort of memory test after every so many boots.The process takes about 30 seconds, and is quite aoying. I would prefer to invoke such a test on demand, rather than have the system decide when to run it. I'm not sure how, or why, this feature started.

How can I remove the automatic ruing of this test?

Thanks,

M..