Make RAM Disk

A utility to quickly and easily create a RAM disk on Mac OS X

  • Download holding area
  • iShowU temp storage
  • Xcode build folder


Make RAM Disk is an application that provides an easy way to create, format, and mount a RAM disk in one shot.

It requires Mac OS X version 10.4 or later. It will not work on 10.3 or earlier.

Make RAM Disk's settings window lets you configure the size and name of the RAM disk, either one-time or until further notice.
The settings window appears whenever you launch Make RAM Disk with the Option key held down.

What's a RAM disk?

Most disks (more accurately, volumes) are backed by some sort of permanent storage, such as an optical disc (as in CD and DVD), magnetic hard disk, or flash memory. In all of these cases, the data on the volume will persist after the computer is shut down, because it's been written to permanent storage. (Sometimes that isn't true, but it's very very rare.)

A RAM disk, on the other hand, has no permanent storage behind it. The data on the RAM “disk” is stored only in RAM (memory), and will be forgotten at shutdown.

Why would I want this?

A RAM disk is at least as fast as your hard drive, but temporary. You can use it as fast storage that won't interfere with hard drive I/O, and for anything you don't want to keep.

A RAM disk is great for screen-recording temporary files; if you use iShowU, see the Storage tab of its preferences. You can also put your Downloads folder (in Safari, Mail, Adium, etc.) on a RAM disk, since you won't always want to keep things you download.

But isn't it possible to lose data if it's only in RAM?

Yes. Don't leave anything on your RAM disk that you want to keep. As soon as you decide to keep something, copy it to some kind of permanent storage, such as your hard disk (especially if you're on a desktop Mac, since you never know when the power will go out).

The danger is less on a laptop, since a power failure isn't as likely to cause the machine to shut down (it will probably just switch to battery power), but there are still circumstances that can lose the contents of the RAM disk. These include kernel panics, depleted batteries, and accidentally clicking the Eject button in the Finder.

How do I use it?

Just run it. By default, it creates a 64-MiB RAM disk named “RAM Disk”.

The application, in a zip archive.
MD5 hash: 189ca211ccb9052e12decd8716411b98
SHA-1 hash: 9e7cdd695e68d567d5bbe64b16dee0341ce399c9
Detached PGP (GPG) signature of using public key ID C6550423.
MD5 hash: 196b92eba439562f45e0d054139412c7
SHA-1 hash: 8c7ca496e24cec1d27e0c33da5c322cdea199946
Objective-C source code and an Xcode 2.4 project, in a bzip2ed tarball.
MD5 hash: a785894c0db8d446027916a8e47a541c
SHA-1 hash: 606e2c627bfa1c20dd170ae7980c61550f9562f1
Detached PGP (GPG) signature of MakeRAMDisk-1.0-source.tbz using public key ID C6550423.
MD5 hash: bb66f7ab8b787aed50f333e7fcfbdae4
SHA-1 hash: bf9071fbefc935b8fff7a979e82dd674cb40aa7e

MD5 and SHA1 signatures were created using version 0.9.7l of the openssl(1) utility, as comes with Mac OS X.

Version history

1.0 (release number 2)

1.0b1 (release number 1)

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