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Re: [ttylinux:314] Unable to built xtools for i686 / 14.1


  I agree. Ext[2-4] filesystems are good for systems on block devices. But the cpio is very suitable for the image booted from network. It do not have preformated the file system size like ext2 image have and it is possible to manipulate in memory with large files. The limit is only given by RAM size. I thing that cpio should be suitable for cdrom image too, because when ttylinux is started from CD, the root file system size is limited now. But I know, everybody can simple mount tmpfs to any directory and use whole RAM.


On Sunday, February 17, 2013 7:35:33 PM UTC+1, djerome wrote:
On 02/17/13 02:29, [email protected] wrote:
> Hi,
>   I am using for my ttylinux boot-from-network and I created root file
> system in cpio format, It is similar to tar, but cpio is used for
> initramdisk in most linux distributions -
> https://www.kernel.org/doc/Documentation/filesystems/ramfs-rootfs-initramfs.txt
>   When I have root file system in ext2 format and I add
> "init=/bin/bash" to kernel command line, system started directly in
> shell. No startup scripts executed. Now I can "mount -t proc proc
> /proc" and in /proc/mount is visible, that not only proc is mounted.
> Devtmpfs and ext2 are already mounted too.
>   But ttylinux started from the cpio initrd do not have pre-mounted
> devtmpfs. Devtmpfs was in 12.1 mounted by process udevd. Now  in 14.1
> udevd do not mount it. I do not know, why udevd change its behaviour.
> I solved this problem in rc.sysinit. I added mount of devtmpfs after
> proc mount.
>   Reg.

A cpio archive is OK for using as an *ephemeral* root file system,
typically from which several kernel modules may be loaded, and
then the cpio archive is released and its memory reclaimed. But a
cpio archived used as an initramfs is not a true file system and I've
found it lacking in some expected capabilities.

For a working root file system, used until system shutdown, a real
file system such as an ext3 is best. If you try to use a cpio archive
for this you will find odd limitations and weird behaviours. A cpio
archive does not function the same as a true file system. At least,
this has been the case in my experience. Maybe newer Linux
kernels handle a cpio archive better than previously. Maybe I did
know how to use a cpio archive. In any case, you are on your
own when using a cpio archive as the working root file system.

Douglas Jerome