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RThom

macrumors newbie
Original poster
Jul 2, 2011
27
0
On the Activity Monitor graph, I'm curious as to the difference between free memory and inactive memory: isn't "inactive" the same as free memory in the sense that it's available to use? :)
 
On the Activity Monitor graph, I'm curious as to the difference between free memory and inactive memory: isn't "inactive" the same as free memory in the sense that it's available to use? :)

Supposably but it isn't the case in practice. I have found apps will continue to page out if there is little free ram and loads of inactive (when it should not be paging out if inactive was free)
 
Thx! So if "inactive" is basically "free" to be used, why the distinction?
 
"Inactive memory is available for use by another application, just like Free memory." So, what am I missing?
 
Thx! So if "inactive" is basically "free" to be used, why the distinction?

The distinction is that if you close an application, the memory that it used goes to inactive. You then open that application up again, and instead of re-loading the app, it uses what was already in memory (as inactive).

So basically inactive ram is memory that is free but an application could reuse it if restarted. The benefit of this is that app opens up much quicker.
 
Thx! So if "inactive" is basically "free" to be used, why the distinction?

"Inactive" contains data that _might_ be useful. For example, if you read a file, the OS might keep the contents of the file cached in "Inactive" memory, just in case you read it again. "Free" memory contains nothing useful.
 
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