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On Thu, Sep 8, 2011 at 4:41 AM, Michał Górny <mgorny@g.o> wrote: |
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> |
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> I'd rather say we should do the work on real issues rather than |
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> imaginate 'separate /usr' problem. Honestly, most of 'advantages' of |
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> separate /usr are just hacks avoiding other problems. |
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> |
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> |
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I guess the irony in my case was that having a separate /usr allowed me to |
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use raid5 without having an initramfs. :) |
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It may have changed, but at least in the past you couldn't have root on a |
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raid5 without an initramfs - you definitely couldn't have it on LVM. So, if |
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you wanted to run LVM on raid5, you had to have a separate root that was |
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raid1 with the older metadata that on-disk looks like a non-raid partition |
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superficially. |
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So, unless you want to waste half your diskspace you need to keep root |
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really small, since raid1 is a lot less space-efficient than raid5. If you |
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want a small root you can't put /usr on it. |
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In any case, I think we need to pick our battles. If every other distro |
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goes one way, then we need to consider whether being different is really |
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adding value, or if it is simply being different. |
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Most distros used an initramfs because they wanted to have one-size-fits-all |
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kernels. Gentoo doesn't do it that way, and hasn't needed initramfs as much |
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as a result. However, in the linux world initramfs has evolved from simply |
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being a way to modprobe the drivers needed to mount root to an extra |
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bootloader that allows for more complex partitioning schemes (btrfs, lvm, |
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raid, etc), disk encryption, and much smarter detection logic (mounting by |
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UUID and not by a device name that is not guaranteed to be stable). |
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I think the proposed direction is sensible. If you have a monolithic kernel |
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and a separate /usr on an otherwise simple setup, then you'll probably just |
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need to emerge an extra package and cat some static file onto the end of |
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your kernel image, or reference it in your kernel config. If you have a |
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complex system then you just run dracut and get automagic bootup logic. If |
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you have /usr on root then you don't need to do anything. |
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The alternative is to spend huge amounts of time maintaining system packages |
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just so that we can be different. |
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Rich |
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