Super User is a question and answer site for computer enthusiasts and power users. 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

Will keeping Activity Monitor running in the background make me incur a significant performance hit? I know things like top in unix (if refreshed often) can use up 100% of the CPU. I ask because I leave it running to monitor my memory usage throughout the day. I often run low on free memory (less than 300MB free) on a 4GB MBP.

share|improve this question

The hit entirely depends on how often you set Activity Monitor to poll the system and what you're working on - if it's the standard 2 seconds on a 2006 2.16Ghz MacBook Pro I saw about a 2%-3% CPU hit (insignificant). At the Very Often setting (0.5 seconds) it was a much more noticeable 25%. Even then depending on what you're doing a process continually eating 25% of your CPU cycles may be a non-issue.

Instead of running Activity Monitor have you considered running a program like iStat menus or Menu Meters or even a script with GeekTool to keep an eye on your RAM usage? By polling for less information it will reduce the performance hit (perceptible or not) that you would have with Activity Monitor (which has the overhead of a GUI, a background daemon, and processing extra information).

share|improve this answer
    
atMonitor is also good. atpurpose.com/atMonitor – neoneye Jul 21 '10 at 12:26

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .