how to tell if your mac is too hot
The sound of the fans spinning up on your mac is never a welcome noise, but it’s usually completely normal. Determining the fan speed without 3rd party software isn’t easy, but not impossible:
do shell script "SD=~/.spindump.txt; rm $SD; spindump 1 1 -file $SD; grep 'Fan speed' $SD; rm $SD" with administrator privileges
Copy and paste the above into your (Apple)Script Editor and run it. You’ll need an Adminstrator password.
However, that doesn’t really tell you what you want to know: is my mac too hot or not? Should I do something about it?
Fortunately, we can get a better idea of the mac’s thermal state (and we don’t need admin privs to do it!), with this script:
The script not only reports the mac’s thermal state, but prints out Apple’s recommended advice, if any. Uncomment the last line of the script to get the result in a display dialog box; otherwise, you can just read the result in the results pane of your script editor.
Featured Image: Flicker
why is my mac running so hot?
’ve previously covered one issue here about overheating macs, but kernel_task is not the only process that can get out of hand. For example, there’s a known issue with some releases of Parallels that can cause a process called prl_disp_service to run up to 99% too, leaving your mac sweating on the desktop even on a cold Winter’s eve!
In general, ‘hot’ issues can be found by looking at what’s going on in your Activity monitor, and solved by quitting (or force quitting) the process. Also, don’t wait to discover these by how hot your mac feels to the touch. Download and install a free copy of smcFanControl and have it running in the menubar. Now you’ll have a reliable means of seeing exactly how hot your mac is. 🙂
However, some processes may not re-start correctly after being quit in Activity monitor unless you reboot the machine or work a bit of Terminal magic. In the case of Parallels, for example, if you’ve identified prl-disp_service as the culprit, the correct solution is to first stop your VM and quit Parallels. Then, open Terminal.app and follow this procedure:
1. Paste this command into Terminal
sudo launchctl stop com.parallels.desktop.launchdaemon
Press ‘Return’. You will be prompted for your password. Note that when you type it in, your typing will be invisible. Press ‘Return’ again.
2. Now paste this command:
sudo launchctl start com.parallels.desktop.launchdaemon
and press ‘Return’.
3. You need to check that the process has correctly restarted before trying to start up Parallels, so one last command:
sudo launchctl list | grep com.parallels.desktop.launchdaemon
The output should look something like this:
36468 – com.parallels.desktop.launchdaemon
The number on the left will be different, but so long as it is anything except 0, you are good to go!
4. Finally, in Terminal, hold down the ‘control‘ key and press the ‘c‘ key at the same time. Now you can quit Terminal and get back to a cool Mac and your Parallels VM. 🙂
You can use these same ‘stop’, ‘start’, and ‘grep’ commands for other errant processes, but you need to find the correct name of the process. You can do this by first noting its name in Activity monitor, then in Terminal, paste:
sudo launchctl list
Look for a launchdaemon that corresponds with the name you found in Activity monitor. Then use the commands above but replace ‘com.parallels.destkop.launchdaemon’ with the name of the process you want to kill.**
**Warning: The sudo command gives you root privileges to the computer and can cause irreparable harm to your OS if used incorrectly. Never mess around with the sudo command unless you have a recent bootable clone of your system.
Why is my mac running so slow?
kernel_task at 103%!!
kernel_task at 103%!!
Overheating on MacBook Pro’s is a rare problem, usually down to nothing more than new users mistakenly thinking the aluminium casing is supposed to feel cool to the touch. However, you know something’s wrong when the glass touchpad feels warm and the fan’s not even stirring…
When Finder and other apps start crashing, what might have been a small concern now starts to look like a real problem. You can try re-booting, but if you find that the reboot takes ten minutes or so and/or the keyboard doesn’t function at the login window, chances are your kernel_task process is running wild. If you’ve still got access to the desktop, you can check this in Activity Monitor, or use Terminal by typing:
Normally, kernel_task won’t take up much more than one or two percent of CPU activity, so if you’re running at over 100% or you can’t get past the login window, its time to do a PRAM/VRAM reset.
1. Power down the machine.
2. Locate the following keys on your keyboard in preparation for Step 4:
‘command’ – ‘option’ – ‘P’ – ‘R’
3. Press the ‘power on’ button.
4. Immediately – and before the grey screen appears – hold down ‘command-option-P-R’ all together.
5. Keep them held down until you’ve heard the start-up chime twice. After you release them you should hear it again, and hopefully your Mac will boot up as it should and with the kernel_task process back to normal.
Tooltip: download and run smcFanControl in your ‘Login items’ to keep an eye on your temps and fan speed in the Menubar. 😉
Have you still got this problem, or found another solution? Let us know in the Comments! 🙂
Why is my mac running so hot?
Why is my mac running so slow?
Resetting the System Management Controller (SMC)
featured picture wormhole by IVIXIVIXVXII