Re: [RFC PATCH 0/4] Persistent device name using alias name

From: Kay Sievers
Date: Fri Jul 08 2011 - 12:15:45 EST


On Fri, Jul 8, 2011 at 17:54, James Bottomley
<James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:

> Yes, we did. ÂEveryone agrees structured logging would be the best long
> term solution. ÂHowever, it's at least 10x the work presented here, plus
> it would be a long process getting everyone to agree.

Maybe even 100 times :)

> This looks like a
> good 95% interim solution and it can be removed when structured logging
> makes everything "just work(tm)".

I don't really see that. I think it does not add any real value on top
of a simple udev logging at device discovery.

You would see that in the log:
[78441.742634]: udevd: sdc: \
disk/by-id/ata-INTEL_SSDSA1M080G2GN_CVPO0363030V080EGN \
disk/by-id/scsi-SATA_INTEL_SSDSA1M08CVPO0363030V080EGN \
disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 \
disk/by-id/wwn-0x50015179593f3038

and know exactly _all_ names and all identifiers of the disk at that time.

Then you see this:
[78441.742634] storage: really bad things happened to: sdc

and with the earlier message we have all we need to know without any
pretty-name hacks.

All that can be done today already with a single udev rule, even on
many years old distros.

> I have also seen a couple of other attempts at structured logging which
> both failed when the people proposing the patches realised how much work
> it actually was, so I'm a bit sceptical we'll ever get there.

The more paper-over we add the more unlikely it gets. That's what I fear. :)

> But hey,
> you have the enthusiasm, propose it as a KS topic to get agreement that
> we should do it and what the format should be and we can go from there.

Sure, I'll do that. If needed, I can even make half or a third of it
possible I guess.

Thanks,
Kay
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