On Mon, 2004-06-28 at 06:50 -0400, Robert P. J. Day wrote: > On Mon, 28 Jun 2004, Wolfgang Denk wrote: > > > In message <Pine.LNX.4.60.0406280600140.3259 at localhost.localdomain> you > > wrote: > > >> that it could be read-only). how hard would it be to automatically > >> have that root FS copied from JFFS2 to RAM and mounted from there? > > > > This makes just no sense to me. > > ok, i'm probably getting confused about something fundamental here. > what i'm after is to have my root filesystem in persistent storage and > available for updates on the fly, hence the notion of partitioning off > a part of the system flash for the JFFS2 version of the root > filesystem. i've done that, so i've solved that problem -- i have a > root filesystem i can mount from a running system and modify. > > now, i could just mount that JFFS2 version of the root fs straight out > of flash, but i get the impression that that would cause a performance > hit.
Why so? JFFS2 is relatively slow to mount, and obviously _writing_ to flash can be slow -- but for normal operation it should be fine. Try it. Personally, I'd just use a JFFS2 root file system for everything. Put your kernel in it too -- RedBoot and u-boot can load kernels from JFFS2, and that means you can atomically update the kernel at runtime too, which you can't do if it's stored in a separate partition (unless you play with having two partitions for it and teach the bootloader to work out which one is valid). -- dwmw2 ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
