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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? :)
 

dukebound85

macrumors Core
Jul 17, 2005
19,117
4,096
5045 feet above sea level
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)
 

RThom

macrumors newbie
Original poster
Jul 2, 2011
27
0
Thx! So if "inactive" is basically "free" to be used, why the distinction?
 

RThom

macrumors newbie
Original poster
Jul 2, 2011
27
0
"Inactive memory is available for use by another application, just like Free memory." So, what am I missing?
 

maflynn

macrumors Haswell
May 3, 2009
73,373
43,264
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.
 

gnasher729

Suspended
Nov 25, 2005
17,980
5,565
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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