Re: "bugfree :)" ramdisk-1.3.4.tar.gz now available
Robert Debath (rdebath@cix.compulink.co.uk)
Thu, 29 Jun 95 00:02 BST-1
From: Drew Eckhardt <drew@poohsticks.org>
> IMHO, a ramdisk block device is the wrong approach to getting a
> memory based filesystem
> - It allways uses a fixed ammount of memory, irregardless of
> how full it is.
> - It uses a "normal" filesystem on it, with the overhead associated
> with that.
> - You need to mkfs any ramdisk you want to use. PITA.
> instead, we want a generic memory based filesystem; which would
> eventually be pageable. We should do something along the lines of
> Sun's tmpfs...
Ahhh, I see, you want userfs's example fs:
- It's completely dynamic
- It's a `filesystem' in it's own right, no block sized overheads
- It doesn't require mkfs
- It's already pageable.
- It needs a little bit of work
But I do also agree with Chad's points, a true filesystem ramdisk has
it's advantages (not least being simplicity) including the mmap stuff,
mmap on a userfs (or even just a tmpfs) would be ... interesting ...
OTOH one of the other examples is what he calls an intensional filesystem
with symlinks that execute a program to fetch the real file...
BTW: I suppose you've noticed userfs is the flavor of the month :-)
NB: I've just patched it for 1.2.10 and am trying to contact the author...
Rob
(Robert de Bath (rdebath@cix.compulink.co.uk))