Re: RAM

[Matt Drew <mdrew redhat com>]

On Fri, 20 Oct 2000, Thomas Dodd wrote:

> Jamin Collins wrote:
> > 
> > IIRC, the 128 Meg limitation was in older kernels.  I believe 6.0 on is fine
> > with larger swap partitions.  (I could be wrong, it does happen from time to
> > time...:-P )
> 
> The kernel was fine, and the swap utilities, but the installer
> didn't know about it, You could get around it with fdisk,
> but DiskDruid was a no-go.
> 
> I think this mail cot started by the
> kernel message about RAM disks.
> I've never really understood what it is
> for , but It's always there but doesn't
> meany much. My system had the same message
> with 32MB, 64MB, and 256MB RAM.
> 
> Check dmesg early in the kernel initialization
> section. It's usually there.
> 
> 	-Thomas

RAMdisks are for the kernel to utilize when the file system is unavailable
or when speed is of the utmost importance.  The most common use for this
is modular SCSI drivers.  There is a catch 22 with a SCSI driver -- if the
driver is on the disk, how does the kernel load it?  The answer is a
RAMdisk, which is a small storage area created in RAM during the boot
process.  This is why the initrd.img is in the /boot directory -
initrd.img is the initial RAMdisk image, and is mounted and available to
the kernel before the filesystem is set up.  If you want to check it out,
you can loopback mount the initrd.img file and look at it.


-- 
Matt Drew
Red Hat Consumer Services (Web Support)