Eric House wrote: > The HOWTOs talk about ramdisks as part of the install process, but not > as something I can use every day. Assuming that I *can* have a ramdisk > on hamm, how do I set it up? >
The file /usr/src/linux/Documentation/ramdisk.txt contains all the info you need. If you haven't installed the kernel sources though, here's the short version: Here's how (assuming your kernel has ramdisk support built in): 1) Decide how big you want your ramdisk to be. Yes, you have to decide. ramdisks can grow dynamically, but filesystems won't. Bummer, huh? 2) Now choose a ramdisk device and create the filesystem with the size you decided on. As root: mke2fs /dev/ram0 size-in-1K-blocks 3) Now mount, season to taste, and enjoy! mount /dev/ram0 /mnt Now read on for other answers... > So far, I've: > put 'ramdisk=2000' in my /etc/lilo.conf file (and run lilo). dmesg tells > me that 16 2000K ramdisks were set up, but free shows that no memory is > consumed so I assume there's another step to making them available. > > I want only one, BTW. :-) You don't need the above. That just tells the kernel to allocate one at startup. This is only necessary if you're going to load the root into a ramdisk and mount it (like you do during installation). > What's next? I'd expect to need to put something in /etc/fstab, but > what's the device file? (/dev/ramdisk?) /dev/ram0, /dev/ram1, /dev/ram2, etc. The number supported is compiled into your kernel, most likely 16. > What if I want more than one? 1 device per ram disk. > And what's the expected/traditional mount point? There isn't. It's like any other block device, mount it wherever you want. > The fstype? Whatever you create on it. I used ext2 above. > Is > there any further configuration to be done? Nope. > How do I use ramdisks once they're created? Just copy my files to the > disk and symlink to them from where they're expected to be? What do I > do to ensure that the files are written to (real) disk on shutdown or > at predefined intervals? Just like any other mounted filesystem. They are never written to disk. That's why they call them "ram" disks. If you want a disk that actually has physical media, why don't you use a real disk? If you're thinking to create a ram disk for performance, don't. Linux agressively uses memory as buffer cache already, so you won't get better performance this way. > I'm so full of questions. Surely there's documentation on this > somewhere. But: Where? -- Jens B. Jorgensen [EMAIL PROTECTED]
