Comments on: Free Up Inactive Memory in Mac OS X with Purge Command

By: 9 Command Line Tricks for Mac OS X You Should Know

9 Command Line Tricks for Mac OS X You Should Know — Wed, 01 May 2013 22:07:36 +0000

[...] purge command forcibly flushes the disk and memory caches, having an effect similar to when you reboot a Mac. [...]

By: craig stothard

craig stothard — Mon, 18 Mar 2013 23:10:37 +0000

hi. thought i wud leave a comment on here as at the top ppl saying… good advice…bad advice etc. here is what happened to my macbook mid 2010 4gig ram. i installed parallels and windows 7. 30 meg of ram left. the system was unresponsive. the beachball thing to the point where i click safari and looked at the spinning ball and nothing for what felt like almost a minute…i searched and found this forum…typed purge and guess what…..800 meg free ram…safari worked as did other apps that previously wouldn’t open for ages. so i think the purge command makes the macbook work.. because before i typed purge…it was unusable. im now gonna search for programmes such as ifreemem and others so this happens automatically. until i decide what app to spend my hard earned money on. ill continue to type purge. cos it works for me. hope this helps some1 out thx. ps mountain lion. thx

By: Manage Web Browser Tab Clutter & Save RAM with OneTab for Google Chrome

Manage Web Browser Tab Clutter & Save RAM with OneTab for Google Chrome — Tue, 12 Mar 2013 18:48:24 +0000

[...] using OneTab to generate the link list, follow it up with a quick usage of the (controversial) purge command, which should free up another 200-500mb of RAM in most cases as it dumps additional caches from [...]

By: Someyunguy

Someyunguy — Sat, 09 Mar 2013 06:14:01 +0000

It’s not the OS that’s the problem with memory management mate – it’s the applications that WEREN’T written by Apple that just “reserve” memory for no good reason (at least the apps I use – I’m a Linux/Mac guy so I’m in Terminal looking at things at the Unix level frequently).

By: jonathan

jonathan — Thu, 14 Feb 2013 14:00:25 +0000

I have a background in operating systems…I can tell you that Mountain Lion suffers from memory mismanagement. Most programmers dont even understand virtual and physical memory, and leave memory leaks throughout their code. The OS should reclaim the pages it can, but the reality is different. Sometimes you have to provide a hint to the OS.

By: Andreas

Andreas — Wed, 13 Feb 2013 11:07:27 +0000

Hi mates.
I have an iMac Intel 3,06GHz Dual Core Duo, 4 Gb Ram with 10.6.8 installed.
My problem is as follows: after I switch it on and run some common applications (iMail, Safari, iTunes) suddenly my available memory starts being eaten up and drops rapidly to around 100 MB or lower and everything starts running like a snail (so to speak). I have installed Onyx, but I cannot find the purge command (there is no memory tab). Any suggestions?
Thank you.

By: Rolland Rice

Rolland Rice — Thu, 31 Jan 2013 18:02:44 +0000

This is exactly what I have been looking for!!! Using Adobe Illustrator with huge files, the MAC’s system memory isn’t purged after the file(s) are closed. This means that if you try to open another large Illustrator file you will get an “File is unopenable” error message. Before knowing this, I would have to quit Illustrator to clear up memory so I could continue working. Thanks so much!

By: Saurabh

Saurabh — Thu, 24 Jan 2013 10:04:51 +0000

i am very thank full to you because your app is really worth for me,its free my inactive memory and my system is start working fast.Thankyou very much…….

By: antonio

antonio — Tue, 15 Jan 2013 22:44:44 +0000

have a ver. for leopard g4?

By: Louis Brunet

Louis Brunet — Sun, 06 Jan 2013 11:11:31 +0000

Thanks a lot for this very usefull trick

By: Bob

Bob — Fri, 28 Dec 2012 20:14:50 +0000

Make sure you have Xcode installed as well as the command-line tools installed. You can find this by opening Xcode, selecting Xcode from the Menu Bar and clicking Preferences. When the preferences menu comes up select the Downloads tab and make sure you are looking at the Components section. You should see a few iOS simulators and Command-line tools. It will either have a button to install it (~150 MB download) or it will say Installed.

By: Bob

Bob — Fri, 28 Dec 2012 20:04:01 +0000

To explain this a little further, purge simply removes all the inactive RAM, or RAM that is not in use, as well as some of the unnecessary active RAM, RAM used up by a program that has not been labeled as inactive (e.g. the previously played song in iTunes, or Pages/Word after you close the application).

The OS has 4 states of RAM, Wired, Active, Inactive, and Free. Wired is what is being used by the OS (e.g. Kernel task), Active is memory used by User and non-essential System applications, Inactive is memory that just hangs there in case you need it for future use, and Free memory is memory that has not been used, or Inactive memory that has been released from the RAM.

Purge isn’t always the best answer for everything though, sometimes you want that cache on the disk for storing information for later use (e.g. downloading a game from the Mac App Store that is larger than your total RAM). Inactive memory *should* automatically cache but when doing a single operation like this it usually starts caching when the RAM gets to about 100 MB or less. It then starts caching to disk and using purge could corrupt your download.

Purge should only be used when you want your system in a fresh state such as playing a RAM intensive game, or if you need to test for memory leaks in a program you are developing in Xcode. (the reason why you need Xcode) Running the purge command after your computer has been on for a while will cause it to run slow for a few minutes because it has to re-address RAM to the applications that are already in use.

I hope this helps, this is the short of the long of what I pulled from Apple’s developer pages on memory management in Obj-C and Cocoa.

By: JHarbin

JHarbin — Wed, 19 Dec 2012 19:28:02 +0000

Check the site before you speak out… Onyx 2.4.0 specifically supports Snow Leopard.

By: me.kon

me.kon — Thu, 06 Dec 2012 17:13:20 +0000

i’m running snow leopard 10.6.6 with xCode installed, still i get ‘command not found’ when running ‘purge’ in terminal, neither terminal manual ‘man purge’ recognises it ! help.

By: EB

EB — Fri, 30 Nov 2012 17:24:45 +0000

purge command is a lifesaver. I could not function without it. When Free memory goes below 100MB my macbook pro becomes unusable. I have to run it several times a day, which really is a mark of bad design in iOS memory management (my opinion only).