When your computer is running a little bit slowly, how can you tell if getting more memory will help you? Here is a simple way to check whether all the memory you have in your computer is being used.
- Go to your utilities folder.
(Click on your desktop anywhere so that the finder is active.
Hold down apple-shift-U, this will open your ‘utilities folder.) - Open ‘Activity Monitor’
- Press apple-1 so that the main window of Utility Monitor is open.
- Click on the ‘System Memory’ tab at the bottom of the window. This will display a little pie graph of how much memory you are currently using.
There are two important items to take note of ‘Free:’ and ‘Page ins/outs:’
Free tells you how much free memory you currently have, the higher the better, and
Page ins/outs tells you how many times your computer has had to slow down because it has run out of memory and needed to use the hard disk to ’switch’ some of it’s memory in our out of use. This really slows down your computer.
If the page in/out count is increasing as you watch it, this is not good, it means your computer has run out of free memory, and so temporarily is using the hard disk as memory. The faster the page in/out count is increasing, the worse the problem – your computer is struggling along and not performing as well as it could. You need more memory.
If you have had lots of free memory since the last time you restarted your machine, the Page ins/outs count will be 0/0. This means your computer had enough memory and has not run out. You dont’ need more memory.
It may be that your Pagein/outs count is high, something like 50431/10850, but steady and this and not increasing. What this means is that some time in the past when you opened a lot of programs, you ran out of memory, but now you have enough. Reboot, check the Pagein/outs count again. It should be 0/0. If it is not 0/0, have a look at it while you open a program or two and see how fast it increases, the faster, the worse your system performance will be.
Here is a screen shot of my computer. My page in/out count is quite high – 66825/697, but I still have 189 MB free, and the page in/out count is not increasing at the moment. This means that sometime since the last reboot, my computer ran out of memory, but currently it is OK. If I reboot the page in/out count will return to 0/0, and stay there unless I go crazy opening lots of programs. I don’t’ need more memory.
To quote from apple:
Moving data from physical memory to disk is called paging out (or swapping out); moving data from disk to physical memory is called paging in (or swapping in)… Extended periods of paging activity reduce performance significantly; such activity is sometimes called disk thrashing.
One more note: Under Leopard rather than giving a ‘count’ of page in/outs, it gives a size in MB of the amount of RAM that has been pages in or out – the numbers are smaller but the same principals apply.
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I just received this by email,
look at how high the page in/out count it!
Time for memory upgrade!
I was googling around to see what excessive paging was as I was worried my mac was on the high side. After 1 day my Page in/outs are at 1376201/486790. Time for a MacPro since I’m already at the 2GB limit on my CD iMac. *Yikes*
Well my page ins/outs count is also very high along with having only 18MB of free memory. I had running Finder, Firefox, Microsoft Word, Preview, Safari, and Activity Monitor. I tried closing Word, Preview, and Safari and now it is up to around 180MB free. Now my question is this…lately I’ve been having slow-downs alot and my computer will freeze for a few seconds and I get the beachball. This happens even after a reboot with only Firefox (and sometimes one more program open). Should I get more memory? If so, how do I know what kind to get. I’m a newbie to the MacBook and OSX.
Thanks!
If it is slow straight after a reboot, and there are no page ins, and there is lots of free memory still, then the slow-down is probably not a memory problem, unless you have Leopard, it needs lots of memory, like 2 Gig at least.
Hello,
I have also been noticing that my computer lately, slows down alot. Usually, I run Mail, iTunes, Safari, Newsfire, Adium and maybe sometimes transmission. I notice that my page in’s and out’s are quite high. Just yesterday it was the highest that I have ever seen. Today I rebooted and immediately after reboot my page ins were 45,023.
I am at a loss on what to do. Alot of times my page outs exceed my page ins after a day of running.
Please help
Hello again, I just wanted to give an update. I rebooted last night before I went to bed. Again right after start up I has an extreme amount of page in’s. Similar to my above comment. Now less the 16hrs later I now have this
Swap 2.01GB(3.00GB)
Page in: 157,558
Page out: 273,764
I really am having a hard time grasping what is actually wrong since I have not had this problem until just recently. My warranty is not yet finished for my iMac.
Please help shed a light on this for me.
Kind regards,
Stuart
@ Stuart,
If your mac is restarted & not running any apps and you are getting page ins/outs make sure there are no applications running in the background such as iTunes helper, iCal helper menu items dashboard widgets third party apps…
They should be listed in the activity monitor window.
It could just be the load that the OS places on your system. You may need more RAM, just keep an eye on the amount of paging and contact Applecare if it concerns you. You don’t say what version of Mac OS or the amount of RAM you have, but more should help. 2 – 4 GB should keep it running smoothly for basic tasks.
PS the Leopard Activity Monitor specifies the paging in MB/GB units, Im unsure if the units are Kb, MB or GB in your comment.
Nice article, it helps clarify what is going on with memory.
Stuart,
how much RAM do you have?
Have you recently upgraded to Leopard?
Wayne
MacBook (Generation 3)
1GB RAM
Free: 11.52MB
Page in: 1218997
Page Out: 736528
Page in/Page out are increasing when I went to a website on FireFox.
Applications in use:
FireFox
Safari
Microsoft Word
Mail
Activity Monitor
Grab
Preview
I also use a lot of Photoshop, iMovie and iPhoto.
For me, it always seems like FireFox that is creating the whole mess. But I need it because of it’s tools that Safari doesnt have.
But my main question is obviously, Do I Need More RAM??
My computer is super slow! My page in/outs are: 74840/25909 and ‘ins’ keep going up. Also the Free is 80 MBs. I just rebooted too? Reboot again? I was just running word and excel and I’m soooo frustrated.
“Free tells you how much free memory you currently have, the higher the better”.
Actually you should never expect “free” to be high. See this article from Apple for more information: http://support.apple.com/kb/HT1342?viewlocale=en_US
recently, I deleted some file and my ibook G4 wouldnt boot. I rebooted it with “Leopard” (it was Tiger before). now it is so slow I have towait onit to open some firefox pages. It is even doing things I didnt comand it to do.
I have 512ram 1.33 processor and 60G HD. what can I do?
Dunwell
I am confused because from your comments it seems as if my system isn’t doing what it is supposed to- my page in is 258.08 and increasing but my page outs is 0 and swap used is 0- is this good or bad? I have 1.04 memory used out of 2 GB but it seems as if an update im trying t o get for my microsoft office is not letting me download because of lack of memory. I am quite confused at this point
I wonder if everyone is forgetting something very simple – what about HOW RAM is used? Is your desktop crowded with items using up that RAM? Keep everything IN your harddrive. ONLY have ALIAS’ on your desktop!~ Keep that RAM free.
The items on your desktop are still on your harddrive, not in RAM.
RAM is the memory in your computer where things are loaded when you open them up.