The day I got my 15" MacBook Pro it was obvious the hard drive is what was limiting the performance. I have done a lot of experimenting with RAM disks since I have it maxed out at 4GB.
For example, intense BitTorrent downloading (and uploading) on a RAM disk frees my hard disk from the constant reads and writes so I can have high speed downloads (and verification of d/led data) and still do disk intensive activities in other applications.
I can't wait for the day where my mass storage can have that kind of speed! (and it looks like it's closer than ever now)
Don't use RAM disks -- it's not 1987, you have a grownup operating system with VM and everything.
As long as you have atimes disabled, the only thing RAM disks will speed up is writes -- recent FS operations are cached in memory automatically (and never paged to disk), so reading a 'warm' file doesn't hit the disk at all.
If you really need such a thing, tmpfs is vastly superior -- it operates directly at the VM page level, instead of idiotically mallocing a ton of address space up front (though I don't think anything like it is available for OS X).
you can mount portions of your ram and use them, but you should be aware that the files need to be put back on a disk before you turn the machine of ;)
For example, intense BitTorrent downloading (and uploading) on a RAM disk frees my hard disk from the constant reads and writes so I can have high speed downloads (and verification of d/led data) and still do disk intensive activities in other applications.
I can't wait for the day where my mass storage can have that kind of speed! (and it looks like it's closer than ever now)