No need to load the whole r/o partition into the ram disk though - I haven't researched the details but I'm thinking you could: - use ZFS - use ZFS's integrated LVM capabilities to include a ram disk device and your r/o partition in the same filesystem, with the ram disk as / and the r/o stuff under a /ro subdirectory - cp -R /ro/* / - because of ZFS deduplication, the ram disk will now be using almost no space because every file is really a pointer to the /ro version. When a file under / is modified, however, the pointer is replaced with the new content.
Pro: a filesystem that is read-only on disk but read-write while running, as loading all the content into a ram disk would be, except the ram disk will only take as much space as the files that are actually modified (a very small portion) Con: more complicated to implement; most systems these days have enough RAM that unless you're requiring a huge USB stick for your read-only content, you don't really need the space anyway. tl;dr: use ZFS's LVM & dedup to create a smart "sparse" ram disk. Just sayin'. -Kz On Wed, Nov 18, 2009 at 13:27, Chad R Mayfield <[email protected]> wrote: > > It has partially been done by a few people. The one that sticks out in my > mind is, http://bcable.net/system.php. Of course this is using a customized > GRML live cd and loaded into a ramdrive each boot, but I don't see why you > could not do something similar with a flash drive. > > --- > Chad R Mayfield > [email protected] > GPG Key: 0C9A026F > http://www.planetmayfield.com/ > http://www.chadmayfield.com/ > http://www.linkedin.com/in/chadmayfield >
