Re: "raw"-ramdisk & cache

Stephen C. Tweedie (sct@redhat.com)
Mon, 29 Nov 1999 13:13:02 +0000 (GMT)


Hi,

On Fri, 26 Nov 1999 08:34:09 +0100, "Ph. Marek" <marek@bmlv.gv.at>
said:

> as far as i can tell, a ramdrive gets handled the same as every
> other block device and is therefore also cached. is there
> (currently) an easy way to stop this?

A ramdisk *is* the cached copy.

> is there something like the unbuffered partition entries, a
> "raw"-ramdrive?

What for? The ramdisk lives in the cache --- there is no other copy
--- and so it cannot be uncached!

If you wanted a different sort of ramdisk you could write one, but if
you want to access it as a block device, it will necessarily use the
buffer cache anyway: that is an invariant of all block devices (the
whole point of block devices vs. character devices is that there is a
uniform buffer cache access mechanism to all block devices).

--Stephen

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/