[systemd-devel] Network Interface Names: solution for a desktop OS

[Xen]

Greg KH schreef op 13-04-16 01:29:
> On Wed, Apr 13, 2016 at 01:20:05AM +0200, Xen wrote:

> All execpt for 4-socket and larger servers.  They take tens of minutes
> in the BIOS and then less than a minute in the kernel/userspace,
> depending on the amount of memory.
> 
> Doesn't your laptop/desktop boot that fast?  If not, you are using the
> wrong distro :)

I have no SSD. Even a 4-rotating-disk raid-10 system using a relatively
new processor (FX 6300) does definitely not boot within a few seconds.

The system I'm on now has a 2.5" 5400 hdd and a mobo/cpu from 2009. Or
2010. I think it takes about 30 seconds before the network is up (by
DHCP probably, is what it means). That's 30 seconds into booting the
kernel, not counting the BIOS.

It seems to take 22 seconds before it loads the nVidia kernel and mounts
/boot and activates swap.

>> Anyway the 3 seconds I mentioned is or would be a relative number.
> 
> You have to define this in a way that will properly work.

I think using timing might not be smart anyway. I don't know.

>> I am sure you can provision that in your boot sequence.
> 
> How?

I would think in the initrd, the most obvious way would be to perform it
right before starting networking. I'm not intimiate on current details
of how booting works. In general you'd think that if networking is a
target, then it would depend on the activation of the renaming/aliasing.

Since the renaming has no impact on anything other than networking, you
can do it right before you start that up.

>> What buses are you mentioning here?
> 
> PCI, USB, etc.

There is a concept in statistics where some (or many) distributions have
a "tail" that is never quite going to disappear.

Even if the probability that something is going to appear in that tail
might at some point be less that 0.00001%, it is never going to be zero,
although it converges on zero.

When you say that probing on the PCI bus never ends, and if we are
talking not about some form of hotplugging, then I really wonder what
you're on about ;-) because I do think the kernel has a limited set of
probes that it can perform, and at some point it is going to quit.

It seems clear that some things are only going to be done once.

So I am not sure what you are alluding to. If there is some theoretical
tail (and it has not to do with hotplugging) I'm not sure if it is ever
going to be relevant here. If there is a theoretical tail, the system
cannot wait for it anyway.