Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

This question already has an answer here:

Process "mtmfs" is using 98% of cpu, heating up the core and runing the fans flat out.

I have quite the process through activity monitor, but does anyone know a longer term solution?

I am running a MacBook Pro 2.2 GHz Intel Core i7 with 8GB RAM and OS 10.7.1

share|improve this question

marked as duplicate by bmike Jan 16 '14 at 12:59

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Is your Console spitting out errors about Time Machine, per this Apple forum? – user479 Sep 2 '11 at 5:04
No console did not seem to be spitting out errors. But I will keep an eye out for this - Thanks – crispinb Sep 28 '11 at 0:39
Are you using a time capsule or some other type of network based destination? I ask because I have the same issue with my personal Macbook at home but not my work MBP. The work MBP uses an external USB drive, but the Macbook uses a network share to a mac mini. – Dustin Oct 2 '11 at 18:35

Presumably you're using Time Machine? mtmfs is Mobile Time Machine file system daemon. Have you tried disabling Time Machine?

share|improve this answer
sudo tmutil disablelocal will switch off this local process, and delete all local copies of data stored in Time Machine. Do look in the console log to check for errors as well, but disabling the local and a reboot should clear the CPU usage if you don't want local backups. – bmike Sep 2 '11 at 13:27
Yes I know time machine is behind this! I have now installed "Time Machine Scheduler" and this has solved the problem. Thanks for your help! – crispinb Sep 28 '11 at 0:37
Please either accept this answer, or add your own to close the question. Glad it could be resolved. – user479 Sep 28 '11 at 5:51
I do have local backups enabled and never got high CPU. Im wondering if the problem is somewhere else ? – latusaki Apr 4 '12 at 12:18

I was running a search on EasyFind and forgot about it - started up Clean My Mac 2 - this is when mtmfs started cranking up my CPU/fan. I quit EasyFind and the CPU % went down immediately. Took a few minutes for fan to slow down. I think maybe the two programs running a thorough search at the same time did it. Haven't had a problem with either one when run alone.

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.