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What is the difference between "Free" and "Inactive" memory?
- Thread starter lamina
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Here's the explanation from Apple -
Wired memory -
This information can't be cached to disk, so it must stay in RAM. The amount depends on what applications you are using.
Active memory -
This information is currently in RAM and actively being used.
Inactive memory -
This information is no longer being used and has been cached to disk, but it will remain in RAM until another application needs the space. Leaving this information in RAM is to your advantage if you (or a client of your computer) come back to it later.
Free memory -
This memory is not being used.
Wired memory -
This information can't be cached to disk, so it must stay in RAM. The amount depends on what applications you are using.
Active memory -
This information is currently in RAM and actively being used.
Inactive memory -
This information is no longer being used and has been cached to disk, but it will remain in RAM until another application needs the space. Leaving this information in RAM is to your advantage if you (or a client of your computer) come back to it later.
Free memory -
This memory is not being used.
on a somewhat related note, the swap file on OS X, does that ever decrease on its own or is the only way to reduce it to restart the computer again?
just curiosity asking. i was recently backing up a dvd of mine and forgot to pay attention to the amount of drive space i had on my laptop...once i got within .5gigs of space remaining my computer all but created a text document telling me that it hated me. i finished the rip, and when i restarted i noticed that i had regained a good chunk of disk space. i assume that was previously being used for the swap file, and that the protest my computer gave was in response to moving in on that territory. eh. whatever the case, i went through and deleted crap i dont need. id like to avoid doing that again in the future.
just curiosity asking. i was recently backing up a dvd of mine and forgot to pay attention to the amount of drive space i had on my laptop...once i got within .5gigs of space remaining my computer all but created a text document telling me that it hated me. i finished the rip, and when i restarted i noticed that i had regained a good chunk of disk space. i assume that was previously being used for the swap file, and that the protest my computer gave was in response to moving in on that territory. eh. whatever the case, i went through and deleted crap i dont need. id like to avoid doing that again in the future.
You should always keep between 6 to 8 GBs Free on the Boot Drive(OS X drive) if its goes under that then the OS will get cranky .. the 6 to 8 GB space is used in Virtual Ram aka Hard drive Ram 
Once the real Ram is all used then Vram kicks in and starts to use the Harddrive space as xtra ram aka Vram
Once the real Ram is all used then Vram kicks in and starts to use the Harddrive space as xtra ram aka Vram
You should always keep between 6 to 8 GBs Free on the Boot Drive(OS X drive) if its goes under that then the OS will get cranky .. the 6 to 8 GB space is used in Virtual Ram aka Hard drive Ram
Once the real Ram is all used then Vram kicks in and starts to use the Harddrive space as xtra ram aka Vram
I have 8GB RAM on Board... what should be my minimum dress space on the Boot Drive?
Try to keep between 5% to 10% hard drive space free.. So on 500GB boot drive - look to keep free around 25GB to 50GB to keep your Mac happy n running smoothly ..
Once you hit that mark - its time to disk cleaning out by trashing old files that you don't need or transferring said files to other drives e.g. cloud storage like dropbox or such service..
Or transfer Boot drive to a bigger drive like 2 or 3 or 4 Terabyte drive ..
My post still valid just adjust 500GB to 128GB = 12.8GB (10%) or 6.4GB (5%)
the largest '12 Mac air drive is 480 GB