i have teh new 1.33Ghz 512 ram 12.1 inch ibook, and i like it alot, but what the heck is inactive memory, its taking anywhere form 20 to sometimes like 200 megs of my memory, that could really be used for other things... like world of warcraft, im going to get another 512 megs @ some point, but i dont want to do that quite yet. If there is a way to get rid of/reduce this, id love to know! (or at least know what it does/is) thanks guys, Mike.
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"Inactive Memory" ??? please explain
- Thread starter mikey12784
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My guess is, but I'm not positive, it's simply memory that can be used by other apps.
Correct me if I'm wrong
Oh, and this thread would be better off in the Mac Help category. Your a noobie... we all learn
Correct me if I'm wrong
Oh, and this thread would be better off in the Mac Help category. Your a noobie... we all learn
Memory types:
Basically, if you open and then close an app, file, etc., OS X keeps it in memory as long as possible in case you open it again. If some other app needs the RAM, OS X gives it away. That's what inactive memory is.
- Free: This is memory available for use immediately by an application or the system.
- Inactive: This is memory that has been used, and could be used again if needed. Swappable.
- Active: This is memory currently in use. Swappable.
- Wired: This is memory currently in use. Not swappable.
Basically, if you open and then close an app, file, etc., OS X keeps it in memory as long as possible in case you open it again. If some other app needs the RAM, OS X gives it away. That's what inactive memory is.
aha, looks like i really do need some more mem, o well, had to happen eventually i guess, must have REALLY sucked for people who had tiger and the old ibooks with only 256 megs to start, that had to be painful. im kinda surprised tho, it doesn't seem very memory efficient, my windows PC is @ less than 95 megs of ram used @ startup, and after runnign stuff for 2 days and exiting all running programs, its only @ like 180-200, and this guy stays @ like 500 used after using stuff, until i restart it. but hey, like i said i really like this machine, so if i need 512 more to make it real nice, 512 more it will get
Not sure why you think you need more RAM... as you use OS X, inactive memory fills up as you use then close apps, resources, etc. It's the SAME as free memory except that, if you restart that app or reuse that resource, it'll start/load vastly quicker. If you have 16GB of RAM, you can fill it with inactive memory. This is a GOOD thing, not a bad thing. Just an optimization.mikey12784 said:aha, looks like i really do need some more mem, o well, had to happen eventually i guess, must have REALLY sucked for people who had tiger and the old ibooks with only 256 megs to start, that had to be painful. im kinda surprised tho, it doesn't seem very memory efficient, my windows PC is @ less than 95 megs of ram used @ startup, and after runnign stuff for 2 days and exiting all running programs, its only @ like 180-200, and this guy stays @ like 500 used after using stuff, until i restart it. but hey, like i said i really like this machine, so if i need 512 more to make it real nice, 512 more it will get
mikey12784 said:aha, looks like i really do need some more mem, o well, had to happen eventually i guess, must have REALLY sucked for people who had tiger and the old ibooks with only 256 megs to start, that had to be painful. im kinda surprised tho, it doesn't seem very memory efficient, my windows PC is @ less than 95 megs of ram used @ startup, and after runnign stuff for 2 days and exiting all running programs, its only @ like 180-200, and this guy stays @ like 500 used after using stuff, until i restart it. but hey, like i said i really like this machine, so if i need 512 more to make it real nice, 512 more it will get
You're fine...on a PC the used statistic is referring to the "Wired" memory, which is stuff that cannot be swapped out. Here's a pic of my activity monitor breakdown right now, with just Firefox and iTunes open (my computer has been on for 9 days):
It says 419 mb used...this is referring to all of the memory that has something in it, whether or not it can be quickly replaced with something else. In fact, I've only got 76 mb of memory that can't immediately be replaced with something else if need be. I almost never hit the point where my memory is maxed out...and if I do the processor and hard drive are usually overwhelmed before the memory maxes out. Now, on my video editing machines I wouldn't pretend to play with anything less than 1gb...but for any normal use of the computer, 500+ is perfectly reasonable.
ahh, well thats not too bad, working on finishing installing WoW so we'll see how that runs, not expecting much, but i normally run it with 2 gigs on my main machine lol. guess we'll find out.
to be expected, its not replacing my machine tho, its just for when i go home or something like that its nice to have something to play wow on still
Well, there are really two kinds of inactive memory: dirty and clean. The difference is if the page has been written out to the backing store.
If a page which has been moved to the inactive list has been modified, but has not been written out to disk, it is referred to as dirty, and it must be paged out before it can be released.
If the page has not been modified (hence the copy in the backing store is still valid), it is clean and can be stolen into the free memory list right away.
All in all, you can either think of it as an 'optimization' or you can think of it as lazy memory management. Its an optimization in the sense that you get the benefit of having 'soft' page faults (moving pages from the inactive list to the active list) over 'hard' faults (paging memory in from the backing store on disk). Its lazy memory management in the sense that you don't need to spend the effort releasing inactive memory until you actually need that space in physical RAM. You put it off until its really necessary.
If a page which has been moved to the inactive list has been modified, but has not been written out to disk, it is referred to as dirty, and it must be paged out before it can be released.
If the page has not been modified (hence the copy in the backing store is still valid), it is clean and can be stolen into the free memory list right away.
All in all, you can either think of it as an 'optimization' or you can think of it as lazy memory management. Its an optimization in the sense that you get the benefit of having 'soft' page faults (moving pages from the inactive list to the active list) over 'hard' faults (paging memory in from the backing store on disk). Its lazy memory management in the sense that you don't need to spend the effort releasing inactive memory until you actually need that space in physical RAM. You put it off until its really necessary.
