[systemd-devel] [PATCH] udevd: SAS: use SAS addr + PHY id in by-path whenever possible.

[Zdenek Kabelac]

Dne 23.9.2014 v 19:55 Kay Sievers napsal(a):
> ----- Original Message -----
>>> We are not applying this patch now. It introduces a complete new
>>> scheme and we do not want to extend the current SCSI code, we only
>>> fix obvious bugs.
>>
>> Fine with me, however not sure what our story should be for years to come
>> regarding SCSI stuff downstream.
>
> Simple as: Don't add new features to systemd/udev, only fix bugs.
>
> SCSI code needs to be maintained by someone who understands it and is
> capable and willing to maintain it in the long run. Systemd/udev
> maintainers lack the experience and cannot do that.
>

Hi

Nice to see there is finally recognized the need to have separate subsystem 
management.

Now - is there some 'plugin'-like interface so we could get an embedded code 
to be executed right with  udev scanning process ?

I can see a tons of code for i.e. btrfs handling to be wired into udev.
I believe this is also something that should be handled externally from udev
(btrfs-progs  udev plugin ?)

Anyway - we would like to eliminate number of forked dmsetup calls
and even further eliminate rule processing when we detect i.e. internal lvm 
device.

When we activate i.e. 1000LVs there is literally storm of forked processes and 
I think we can do much better.

Since there is already 'blkid' being built-in - we could solve problem 
partially by enhancing blkid detection - but still there are some things we 
can't handle within  blkid (parsing DM  names)

It would be nice to have some plugin API here where we could avoid forking 
process to do rather trivial 'string-manipulation' stuff.


> New features need to happen in an existing or new storage related-package
> and not in the systemd/udev code base.

So any plans on udev plugin API  (since rules are simply way to slow and 
inefficient)

Zdenek