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guitargoddsjm
Sep 6, 2011, 08:59 PM
As I write this, kernel_task has ballooned to 682.8 MB of real memory.

I noticed kernel_task yesterday when I had ~2.5GB of free memory (which is odd, because I recently upgraded to 8GB). I quit every application and restarted with "Reopen windows" unchecked. Immediately after restart, kernel_task was 488.1 MB.

What's causing this? I have enough RAM that it doesn't matter too much, but I'd really like to be able to prevent this if possible.



Galaxas0
Sep 7, 2011, 12:03 AM
Hey, just noticed you cringing about that kernel_task. Just saying, but it's easily 700MB over here in real memory on a late 2008 MBP. No worries?

iBookG4user
Sep 7, 2011, 12:08 AM
That's actually not too bad, the kernel is taking up 1.88GB of RAM on my Mac Pro.

Lokheed
Sep 7, 2011, 12:18 AM
So I'm curious. What do you guys do? Stare at Activity Monitor all day or something?!?

Leave it alone. Mine's 653 MB. Obviously this is normal. Put Activity Monitor away and just use your computer. Seriously. How many threads on this topic do we need?

From the name of the executable, it sounds like it does pretty important stuff. Needs RAM. What's the problem? :rolleyes:

PS: No one's going to have a definitive answer btw. Apple engineers don't talk about that stuff, and no one else is going to know squat. Like asking "what's the meaning of life"óno one knows bro!!!

iBookG4user
Sep 7, 2011, 12:51 AM
So I'm curious. What do you guys do? Stare at Activity Monitor all day or something?!?

Leave it alone. Mine's 653 MB. Obviously this is normal. Put Activity Monitor away and just use your computer. Seriously. How many threads on this topic do we need?

From the name of the executable, it sounds like it does pretty important stuff. Needs RAM. What's the problem? :rolleyes:

PS: No one's going to have a definitive answer btw. Apple engineers don't talk about that stuff, and no one else is going to know squat. Like asking "what's the meaning of life"óno one knows bro!!!

Kernel_task is the operating system. Couldn't tell if you knew or not from your post.

Lokheed
Sep 7, 2011, 02:24 AM
Kernel_task is the operating system. Couldn't tell if you knew or not from your post.

Yeah, I've read this (http://bleepsoft.com/tyler/index.php?itemid=43).

An an excerpt:

Documentation on kernel_task is sparse at best, but from what I can glean from the darwin-drivers@lists.apple.com mailing list that I'm on, it seems to be the basic (virtual/)memory manager for Mac OS X on top of Mach. From the best I can tell, this is similar to the sigma0 concept with the L4 microkernel. There needs to be some underlying task on top of any microkernel (from the best of my understanding) to dole out resources, like pages of memory, to the userland processes. Unfortunately, I can't really find documentation for much about kernel_task, but I'm relatively confident in telling anybody that's read this far (all both of you!) that kernel_task is responsible for handling the allocation of pages of memory in the Xnu kernel (Mach+IOKit+whatever else Apple threw in), which would explain why it has an amazing amount of threads.

So it's not the operating system... it's much deeper than that. And an operating system is a collection of apps, low-level programs, extensions, etc. It is an amalgamation of things, like a house (walls, windows, floors, etc.).

yjchua95
Aug 24, 2012, 10:35 PM
I've also got problems with it. Immediately after quitting VMware Fusion 5, I saw that kernel_task was taking up one helluva lot more CPU power, making the fans spin up. It also screwed up my Ethernet connection (kept trying to disconnect from the ISP, but failed). All I could do was curse and reboot.

throAU
Sep 2, 2012, 09:04 AM
I suspect it is disk cache.

My advice for people freaking out about memory usage on blah process:

close activity monitor. if your mac chugs, buy more memory.


use activity monitor to check CPU usage, and/or close hung apps. leave the OS to do its thing, if it needs memory it will use it.

"free" ram is wasted ram. ideally a modern machine should be consuming all of the available ram for disk cache if no application requires it.