[Mageia-dev] Please test: initscripts+systemd in updates_testing

[Colin Guthrie]

'Twas brillig, and Thomas Backlund at 31/10/11 19:01 did gyre and gimble:
> Colin Guthrie skrev 31.10.2011 19:47:
>>> Just have initramfs mount / and /usr, no need to merge.
>>
>> Yes, this is exactly what is intended, but it depends on the use case:
>>
> 
> Then I have misread something somewhere along the way... :/

Yeah the link Olav provided (
http://www.freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
) is certainly worth reading if you've not already done so. The "Going
Forward" section in particular starts with this quote:

"/usr on its own filesystem is useful in some custom setups. But instead
of expecting the traditional Unix way to (sometimes mindlessly)
distributing tools between /usr and /, and require more and more tools
to move to /, we now just expect /usr to be pre-mounted from inside the
initramfs, to be available before 'init' starts."

>> For simple installs, such as on my laptop or typical "desktop" linux,
>> then having separate / and /usr is something I've specifically avoided
>> for just about ever (I sometimes have separate /boot for "complicated
>> rootfs" reasons and I almost always have a separate /home, but other
>> than that, I like to keep my desktops/laptops simple). In other words
>> there just are not sufficient benefits in doing this.
> 
> Yes,
> I agree for the desktop/laptop/pad/ use there is no need for splitting
> besides /home and maybe separate /boot if you want to use encryption.

Nod

>> But on the server, especially on a farm of servers with a potentially
>> shared /usr across several machines, then yes, keeping it as something
>> that can be mounted by the initramfs is perfectly feasible. This is a
>> specific use case that Lennart + Co are trying to design for.
>>
> 
> Ok, this is exactly the part that have raised my concerns that it was
> about to be "forgotten" in favour of "simplicity".
> 
> Server installs usually want to be more "free" to finetune.
> 
> Another use case is to be able to split up the system on more harddisks
> to even the load on the disks.
> 
> And yet another is simply to get more space depending on hw.
> (yes I know lvm exists but it's also an extra layer / point of failure
>  that is not always worth it)

Totally agree about LVM (and to a lesser degree the RAID layer)... I'm
looking forward to btrfs which merges in the RAID layers and (I think -
I've not fully read up on it) the LVM functionality too.

Currently, I've found performance really takes a hit with my RAID+LVM
setups... 40M/s write speeds where as just plain RAID was getting closer
to 160M/s... this is likely in part due to 4k sector sizes too of
course. But I digress!

> But if this part is the "some specific usecases" then I guess I need to
> start re-reading some stuff :)

:)

Col

-- 

Colin Guthrie
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http://colin.guthr.ie/

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