Confused about Activity Monitor CPU stats

I have found at least one case where the CPU summary usage stats seem inconsistent with the per-process stats also posted.
For example, I had noticed that under certain circumstances, the kernal_task was pegged at ~7.9% (only varying a few tenths of a percent) and yet the average "idle" CPU usage is consistently ~97 to ~98 percent (I would have expected ~92 to ~93 percent given that all but the kernel_task were pretty much idle during the observation period).
Clearly, the summary averages are being calculated differently (over a different time scale???) than the line item process averages.
This is not the pressing issue of the century .... still, I'd like to get a better idea of what these metrics mean.

Let me guess ... if I've got 2 dual proc's it's 400% and 2 quad proc's it's 800% ????
So the line item CPU stats are per processor, and the overall usage is calculated over 4 processors ?? (That roughly corresponds to seeing one task showing 8% loading ... but overall loading at 2% ... which is what I observed.)

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Activity monitor/CPU

I was just wondering what "user"s listed i should be allowed to run under activity monitor within cpu and how to locate them in a file if i want to rid the usage from my macbook..i know that's kind of vague but i know as much about computers as the next guy..

You really don't need to worry about it unless you get a runaway process and you will see that in CPU %. I normally keep mine showing All Processes to catch anything like this occurring.

"Simple" question about Activity Monitor

When Activity Monitor displays percentages, is that percentages relative to what else is running, or is that percentage of the CPU's processing capacity? Something that is using up 30-40% of the CPU's processing capacity is a lot more intense than something that is using 30-40% of the CPU's activity AMONGST the other threads running.
So which is it? Percentage of the CPU's processing CAPABILITY or percentage of what the processor is chewing on right now - regardless of how much more it could chew on.
This will help us decide if our current xserve (1G, 1CPU, G4) is adequate for our needs or we're constantly maxing out the processor and need to look for a faster server. I don't want to replace an older, but still adequate system just because newer is obviously faster.

It's entirely possible for a process to use more than 100% of a CPU.
In the case of a dual-CPU machine you could use up to 200% (100% x 2 CPUs).
In the case of a quad-core machine (2 x dual-core CPUs) you could see up to 400% (100% x 4 cores).
An 8-core server could see up to 800%
You see, the 100% mark is based on each CPU core, not all cores combined. I guess that wasn't clear in my earlier response.

Activity monitor CPU history now shows single graph in Floating window - how to restore display of all eight (8) cores?

Since restarting, the Activity monitor floating CPU history Window now shows all eight cores collapsed into one. This is NOT the behavior I expected after doing some research and finding this article OS X: Activity Monitor shows one CPU Usage graph on systems with more than four cores - Apple Support
Not a show stopper but I've been investigating performance issues on a new machine and this "new" behavior has me flummoxed and suspecting a newbie error.
Thanks!

Well, after a few more reboots and a therapeutic OS X 10.10.3 reinstall - troubleshooting some really sick performance issues. This problem has gone away. I am no longer staring a beachballs on my 8 core mini with 16GB RAM and an SSD boot drive. Should be good for a while :-)

Question about Activity Monitor

I was looking at activity monitor to see how things were running and I noticed on %CPU I was between 125%-175%. Can it do this because it is a dual-core processor? And is this bad/a lot if that is the only program running?
Thanks,
John

Post an image of your Activity Monitor. This is mine:
Make certain that you set it to show ALL PROCESSES and % CPU is set to display values from high to low.
Ciao.
Ignore the red circle.
Message was edited by: OGELTHORPE

A question about Activity Monitor!

Hi all
Is there a way to know the MBP temperature (any) by using Activity Monitor? or Terminal?
I use iStat Menus but I need to know for my information.
Thanks

No. The Terminal shell contains no commands to access temperatures directly hence the need for software like iStat.

IMac using 100% of the CPU, but no processes in Activity Monitor show usage over 3%. What's going on?

This iMac is about 5 years old. It has the 2GHz Intel Core 2 Duo processors, 2GB RAM, and is running 10.8.5. After rebooting the machine, CPU usage is low. After about 30 seconds, when using Activity Monitor, CPU usage bumps up to 100% and stays there without budging. When viewing the CPU tab near the botom, % User is about 95+%, and % System makes up the other 5%. They change slightly every second. The problem is, if I sort my Processes by % CPU, the largest user is Activity Monitor with around 2.3%. Everything else is at 0.0%. So there's something weird going on causing the CPU to max out and run hot, but I can't figure out what's causing it. Checking for applications to force quit doesn't show any issues, and repairing permissions doesn't do anything. Is there any way to figure out what's going on? I read about how to reset the System Management Controller, is this something I should do? Thank you for ANY help, it's driving me crazy!
EDIT: I figured it out! Browsing All Processes, I'm running a folding@home program, but I thought I uninstalled it! The process is called FahCore_a4. Is there any way to prevent it from showing up on boot? I want to get rid of it but I deleted the applications!

Be certain to check that you are viewing "All Processes" as opposed to "My Processes"

Mountain Lion 10.8.3: Dock shows 100%+ CPU in Activity Monitor

I upgraded my 'early 2008' MBP from 10.8.2 to 10.8.3 last week. Memory use seems to have increased with no real change in application usage — .CPU utilization seems similar, too. I have been watching Activity Monitor + vm_stat to see if I could identify any issues. I just noticed that the Dock process shows 100% CPU utilization in the detail section — even though the Activity Monitor summary stats show plenty of idle CPU cycles available. Swap activity is minimal — this all makes me question the validity and/or accuracy of the detailed stats shown in Activity Monitor. Any input or comment from the community?
TIA...
P.S. Activity Monitor screen shots are below. And no, I'm not running Parallels as per prior discussion https://discussions.apple.com/message/15596756#15596756 from 2011.

My $HOME/Library/Preferences folder contained only two com.apple.dock.* files:
com.apple.doc.plist w/current date timestamp
com.apple.doc.plist.KBPCAn with two-month old date timestamp
Detailed examination of the com.apple.doc.plist parameters seemed to be correct with nothing abnormal.
The killall Dock command suggested by Kappy seemed to address the 100%+ CPU at first, but then it returned.
Three consecutive full system shutdown/restart cycles seems to have eliminated Activity Monitor showing the Dock process running @ 100%+ CPU after 24+ hours of operation. No changes were made to the content of com.apple.dock.plist. My best guess at this point is that my system's Dock process may have had a memory leak-type issue that is neither traceable or reproduceable at this point.
The Activity Monitor issue variance (Dock process detail @ 100%+ CPU despite the summary record showing idle CPU cycles available) isn't explained. It seems to me that the sum of the detailed Activity Monitor records should match the summary pie chart information presented.
Thanks to Kappy for the input and suggestion. Further comment/discussion WRT the Activity Monitor issue is most welcome...

Etrecheck vs Activity Monitor

Hi,
I've noticed (and not for the first time, BTW) that the results of Etrecheck don't match those of Activity Monitor on my Mac (the pics below). For example, Etrecheck displays CPU use percentage as followings: for WindowServer 3% while Activity Monitor shows 0.7%, further on, for Activity Monitor utility these figures are 0% and 0.9% respectively, etc (the others you may want to compare on your own). If you look at the Memory use then you'll see these figures determined in a unknown way but tied somehow up with just Virtual Memory, however judging from Apple's notes on the subject of the latter OS X Mavericks: About Activity Monitor This is not an actual consumption of RAM resources and it size is determined by the author of the app.
So why it's decided to go with this parameter is totally unclear for me, and how to draw conclusions with regard to AM utility is unclear too. It gives different values for all types of RAM than AM does. Make sure yourselves:
How can I be sure Etrcheck displays data correctly?

Activity Monitor updates every 5 seconds or so. The CPU % will fluctuate over time. The EtreCheck is a single slice of time. Your observations are meaningless.
If you monitor the WindowServer percentage, you will see that it fluctuates up and down, especially if you move the cursor around.
P.S.
You would benefit by adding more RAM:

How to clear activity monitor

testing suport system.

Hi shashahaa,
I'm sorry, I'm not sure if you are asking the question or just testing the posting functionality of the forums, but if you are having issues with or questions about Activity Monitor, you may find the information outlined in the following article helpful:
How to use Activity Monitor - Apple Support
Regards,
- Brenden

Activity Monitor command-line equivalent

Hi,
Is there a way to gather all the informations that we can find in the Activity Monitor (cpu, memory, open file-descriptors for each process) via the Terminal ??
In fact, I am looking for a procfs (/proc) equivalent...

Hello ccharbo,
You could use the top command. Does procfs (/proc) not provide all the information you are looking for?
[Mac OS X Manual Page For top(1)|http://developer.apple.com/mac/library/documentation/Darwin/Reference/Ma nPages/man1/top.1.html]
B-rock

When I set up Contacts on iCloud, Contacts on my Mac consumes about 100% of a CPU, per Activity Monitor. Does that make sense?

I don't think this should be happening, but I haven't been able to find any reference to such a situation in Apple Support or on Forums.

I'm trying to do this. I unchecked Contacts, restarted my Mac and lo and behold, Contacts was rechecked! I unchecked it and checked Activity Monitor. By the time I returned to System Preferences, Contacts was rechecked. This happened 3 times. Now it has remained rechecked, AddressBookSourceSync is consuming over 90% of a CPU (mostly over 95%). I'm letting it go for about half an hour. I'm debating whether to let it go and see if it settles down (no evidence that it will). CPU time is over 30 minutes now. I think I'm going to quit (or Force Quit) AddressBookSourceSync, follow the suggested steps and see what happens.

Getting messages "startup disk is full" and activity monitor is showing "syslog d" is using a lot of CPU. I'm planning on getting more memory for my late 2008 model Macbook but wondering if there's something that is causing problems that I can also fix.

I had closed out of all of my programs but heard the internal fans running so I checked the activity monitor. It shows syslog d as the top process using the CPU right now. I have no idea what that means.
I read a thread about the startup disk being full and how you can free up memory. I have an airport extreme so TimeCapsule is backing up everything. I do have a bunch of pictures on iPhoto on the laptop; could move those to another location but I'm a little gunshy. I know they are on the TimeCapsule but I would like to save them to a second place before deleting from laptop just to be sure. I went through several things yesterday and emptied trash, etc. I wasn't able to locate the hidden files that the thread about the startup disk being full was referencing --- they were talking about large emails that were causing processes to happen taking up the CPU.... I wasn't able to find out if that was the case for me.
Also I'm going to look into getting another 2MB of memory and installing it on the Macbook, so I can upgrade to the latest OS. Anyone have an idea if that is worth the $$$ over buying a new laptop? Or anyone have ideas as to where to buy memory, etc.
Any ideas - help!

Go step by step and test.
1. Start up in Safe Mode.
    http://support.apple.com/kb/PH11212
2. Empty Trash.
   http://support.apple.com/kb/PH13806
3. Disk space / Time Machine ?/ Local Snapshots
Local backups
   http://support.apple.com/kb/ht4878
4. Delete old iOS Devices Backup.
    iTunes > Preferences > Devices
    Highlight the old Backups , press “Delete Backup” and then “OK”.
    http://support.apple.com/kb/HT4946?viewlocale=en_US&locale=en_US
5. Re-index Macintosh HD.
    This will take a while. Wait until it is finished.
    System Preferences > Spotlight > Privacy
    http://support.apple.com/kb/ht2409

MBP with 10.6.8: CPU usage high, no responsible processes shown in Activity Monitor. What causes this?

After using my computer for some time, CPU usage climbs to about 90% (ca. 65% user / 26% system) and fans run at high speed, but there is no processes that seem to use CPU (other than Activity Monitor itself ~1%).
This has happened a few times recently. It happens when I've used my computer for some time, hours or a couple of days (I usually put my computer to sleep when not using it but rarely shut it down). I've tried to quit all running apps incl. Growl, Dropbox, and anything that could be responsible to this but with no results. Putting computer to sleep for a long time doesn't help, cpu usage will climb instantly after wake up. Restarting system is the only thing that helps.
Most of the time I use my laptop with external monitor, lid closed and connected to power supply. When experiencing this, opening the lid causes fans to slow down, but CPU usage remains high and battery drains quick.
Any ideas what might cause this?
My MBP is 15" model with Core 2 Duo 2,66 GHz (MacBookPro 5,3), OS X version is 10.6.8, all available updates are installed.

Perform a SMU reset.
https://support.apple.com/kb/HT3964
Remove the anti-virus, it's running a root level process all the time that's taking your CPU and it's not necessary as there are no Mac viruses, Apple has the trojan angle covered already.
Always on anti-virus on a Mac is always a source of problems, also is MacKeeper, uninstall that here if you have it.
http://applehelpwriter.com/2011/09/21/how-to-uninstall-mackeeper-malware/
If you need to clean the Windows filth off PC files, then use the free, run as you need, ClamXav.
http://www.clamxav.com/
It seems your machine is used in a corporate enviroment, thus likely a rule that anti-virus must be used, you can avoid high CPU usuage by using the ClamXav instead.

Newbie having problems with noisy fan and high CPU usage in Activity Monitor

I am new to the world of Apple and have got my hands on a hand-me-down PowerBook G4 version 10.4.11. It works fairly well for everything but the Internet.
One of the first symptoms i noticed was that watching stuff on youtube was slow and jumped a lot. I checked a few things out and looked the CPU usage in activity monitor and this was about 80% to 100% when on youtube or even moving from page to page. I'e tried loads of stuff including repairing disk permissions, emptying caches and relaunching finder when the preferences file is on the desktop (not really sure what that was supposed to do).
The next thing I discovered was that if i disconnected the laptop from the mains and played youtube and some other applications the whole thing would go into sleep mode very quickly. I have got temperature monitor downloaded now although I already know it is getting very hot.
PS when it heats up the fan turns on because I can hear a whirring sound...
Would really appreciate some insight into this as it seems to be a good runner otherwise.
PS2 I have loads of free space left in the disk usage tab in activity monitor.
Big thank you in advance

Welcome to the world of PowerBook!
One of the first symptoms i noticed was that watching stuff on youtube was slow and jumped a lot. I checked a few things out and looked the CPU usage in activity monitor and this was about 80% to 100% when on youtube
Virtually no G4s are dealing well with web video anymore. The video technology used by modern developers puts a huge strain on a G4 processor. As this a choice made by coders, there is not much you can do about it. Some people suggest adding RAM but the effect is marginal considering it's the processor that's taxed.
Notebooks get hot. The fans in my 1Ghz 17-inch PowerBook from 2003 kick in between 130 and 140°F. The danger point is not until in the vicinity of 100F so don't sweat it to much. Make sure you do not cover the case bottom by setting the computer on a thick cloth placemat, pillow or other bedding item, or on your lap without a lapboard. The bootom of the case is part of the heat dissipation system and needs air under it to work
A lot of PowerBooks have, by now, lost some or all of their "feet" that gve a little space under the case. Don't bother looking for official replacements--get the silicone door/drawer bumpers from the hardware store that stick on. I found some about 3/16" thick that let more air under my PB thatn the mostly missing originals.
The next thing I discovered was that if i disconnected the laptop from the mains and played youtube and some other applications the whole thing would go into sleep mode very quickly
Your battery is likely dead from old age. Batteries only last about 2-3 years. You are seeing a sign of the battery lacking sufficient remaining capacity to run the computer. Get this utility:
http://www.coconut-flavour.com/coconutbattery/
(you'll need the 2.6.6 version for Tiger) and post what is says about "Health" and "Cycles."

Confused about Activity Monitor CPU stats

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