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Joshua Kinard posted on Tue, 13 Mar 2012 20:16:10 -0400 as excerpted: |
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> On 03/13/2012 07:54, James Broadhead wrote: |
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> |
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>> I believe that the Art of Unix Programming* says that /usr was the |
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>> result of the original UNIX 4MB hard disk becoming full, and that they |
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>> chose /usr to mount a second one. Every definition since then has been |
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>> an attempt to justify preserving the split. |
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> |
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> Sounds like how a lot of UNIXy things came into being. This is why I |
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> think /usr should be merged back into /, not the other way around. |
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> Although, both approaches essentially achieve the same effect in the |
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> end, once you move /etc and a few other bits, then point the kernel at |
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> "/usr". |
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I've seen it pointed out that in initr* based systems anyway, the "new" |
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rootfs is effectively taking the role the old initrd tmproot did, it's |
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only there in a bootstrapping role, no "running system" content at all, |
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except that instead of using pivot_root or whatever to get off it once |
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the system early bootstrap is done, it remains the mountpoint used by |
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everything else on the running system. |
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That's rootfs's only modern role, according to these folks, providing the |
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mountpoints for everything else. |
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And with an assumed initr* based setup, it all "just works". Rootfs can |
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in fact be entirely virtual, tmpfs or squashfs or whatever, setup only in |
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the initr*, with only a few minimal early-boot config files, the modules |
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necessary to boot the rest of the system, etc, as content, and those |
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quickly over-mounted with the "real" system -- note that /usr/etc can be |
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bind-mounted over the boot-time-stub /etc too, so literally, post-initr*, |
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the ONLY part of rootfs operationally visible is the mountpoints used by |
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everything else. |
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THAT is why they're moving /bin, /sbin and /lib to /usr rather than the |
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other direction. rootfs will be ONLY a mountpoint, with even /etc/ being |
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bind-mounted from /usr/etc, and all system data unified on /usr, |
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including /etc. |
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Viewed from that perspective, the direction of the "unification", |
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everything formerly on rootfs moving to /usr, so rootfs' only function is |
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providing the mountpoints for everything else, has a certain logic to |
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it... |
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And they don't care about non-initr* based systems any more than they |
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care about non-Linux systems or for that matter, non-systemd Linux |
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systems. That's outside their operational universe. Other people are |
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welcome to continue working with "legacy" systems if they want, but Linux- |
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only, systemd-based, initr*-based systems are the only thing they're |
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interested in supporting, themselves. |
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|
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman |
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