Move Chrome, Safari and iTunes Cache to Ramdisk.

osx_ramdisk.sh

#!/bin/bash

# Size at the end is * 2048 where 2048 = 1 MB, so 1572864 = 768 MB
#DISK=`/usr/bin/hdiutil attach -nobrowse -nomount ram://1572864`
DISK=`/usr/bin/hdiutil attach -nobrowse -nomount ram://2097152`

/usr/sbin/diskutil erasevolume HFS+ "RamDiskCache" $DISK

CACHEDIR="/Volumes/RamDiskCache/$USER"

# Chrome Cache
/bin/rm -rvf ~/Library/Caches/Google/Chrome/*
/bin/mkdir -pv $CACHEDIR/Google/Chrome/Default
/bin/ln -v -s $CACHEDIR/Google/Chrome/Default ~/Library/Caches/Google/Chrome/Default

# Chrome Canary Cache
/bin/rm -rvf ~/Library/Caches/Google/Chrome\ Canary/*
/bin/mkdir -pv $CACHEDIR/Google/Chrome\ Canary/Default
/bin/ln -v -s $CACHEDIR/Google/Chrome\ Canary/Default ~/Library/Caches/Google/Chrome\ Canary/Default

# Safari Cache
/bin/rm -rvf ~/Library/Caches/com.apple.Safari
/bin/mkdir -pv $CACHEDIR/Apple/Safari
/bin/ln -v -s $CACHEDIR/Apple/Safari ~/Library/Caches/com.apple.Safari

# iTunes Cache
/bin/rm -rvf ~/Library/Caches/com.apple.iTunes
/bin/mkdir -pv $CACHEDIR/Apple/iTunes
/bin/ln -v -s $CACHEDIR/Apple/iTunes ~/Library/Caches/com.apple.iTunes

# Spotify Cache
/bin/rm -rvf ~/Library/Caches/com.spotify.client
/bin/mkdir -pv $CACHEDIR/Spotify
/bin/ln -v -s $CACHEDIR/Spotify ~/Library/Caches/com.spotify.client

/usr/bin/chflags hidden /Volumes/RamDiskCache #Hide RamDisk directory

Good script work very well, can you help me to start at boot in Yosemite?

@nischu7

when I turn on programs I can't see anything in Finder when I look at RamDiskCache folder...
is there sth wrong with the code?

I created sth like this:

!/bin/bash

Size at the end is * 2048 where 2048 = 1 MB, so 1572864 = 768 MB

DISK=/usr/bin/hdiutil attach -nobrowse -nomount ram://819200

/usr/sbin/diskutil erasevolume HFS+ "RamDiskCache" $DISK
CACHEDIR=“/Volumes/RamDiskCache/$USER“

Chrome Canary Cache

/bin/rm -rvf ~/Library/Caches/Google/Chrome\ Canary/*
/bin/mkdir -pv $CACHEDIR/Google/Chrome\ Canary/Default
/bin/ln -v -s $CACHEDIR/Google/Chrome\ Canary/Default ~/Library/Caches/Google/Chrome\ Canary/Default

Safari Cache

/bin/rm -rvf ~/Library/Caches/com.apple.Safari
/bin/mkdir -pv $CACHEDIR/Apple/Safari
/bin/ln -v -s $CACHEDIR/Apple/Safari ~/Library/Caches/com.apple.Safari

iTunes Cache

/bin/rm -rvf ~/Library/Caches/com.apple.iTunes
/bin/mkdir -pv $CACHEDIR/Apple/iTunes
/bin/ln -v -s $CACHEDIR/Apple/iTunes ~/Library/Caches/com.apple.iTunes

Spotify Cache

/bin/rm -rvf ~/Library/Caches/com.spotify.client
/bin/mkdir -pv $CACHEDIR/Spotify
/bin/ln -v -s $CACHEDIR/Spotify ~/Library/Caches/com.spotify.client

Chrome Cache

/bin/rm -rvf ~/Library/Caches/Google/Chrome/*
/bin/mkdir -pv /Volumes/RamDiskCache/Google
/bin/ln -v -s /Volumes/RamDiskCache/Google ~/Library/Caches/Google/Chrome/Default

Hide RamDisk directory

/usr/bin/chflags hidden /Volumes/RamDiskCache

@transalp95
To create a startup script in OS X you'll have to build an Automator app.
Start Automator. With CMD + N to you'll create a new workflow. In the first dialogue you choose for creating an app.
Then you'll search for 'shell'. Drag it. Paste this script. Save it - probably to your app folder.
In System Settings go to Users and groups. Click on Log-on objects and add your recently created app. That would do it.

How would I move Safari Cache back to original folder? I've deleted the RAM Disk but com.apple.Safari isn't in Library/Cache after reboot.

@nischu7 if you don't mind answering, the /dev/rdisk2 size of 1024 MB is ~50% the size of the ram://2097152. That seems to be consistent for various different file systems. Is there a short explanation the size difference, or can you recommend what I might read up on to better understand what's going on?

$ DISK=`/usr/bin/hdiutil attach -nobrowse -nomount ram://2097152`
$ /usr/sbin/diskutil erasevolume HFS+ "RamDiskCache" $DISK
Started erase on disk2
Unmounting disk
Erasing
Initialized /dev/rdisk2 as a 1024 MB case-insensitive HFS Plus volume
Mounting disk
Finished erase on disk2 RamDiskCache

Found the answer using diskutil info $DISK

....
Total Size:               1.1 GB (1073741824 Bytes) (exactly 2097152 512-Byte-Units)
....

Hi I'm wondering if I put this script in my ~/Library/StartupItems directory, will it run at startup?