Gentoo Archives: gentoo-dev

From: Jaco Kroon <jaco@××××××.za>
To: gentoo-dev@l.g.o
Subject: Re: [gentoo-dev] rfc: switching default udev provider for new systems to udev
Date: Sat, 08 Aug 2020 22:29:14
Message-Id: 0821d944-4941-7e75-01bf-16bdf96e89d0@uls.co.za
In Reply to: Re: [gentoo-dev] rfc: switching default udev provider for new systems to udev by William Hubbs
1 -----BEGIN PGP SIGNED MESSAGE-----
2 Hash: SHA256
3
4 It actually works is enough reason for me.  Was forced to migrate a
5 > bunch of systems not six months back from systemd-udev to eudev because
6 > systemd-udev is absolutely terrible w.r.t. race conditions resulting in
7 > lockups that kept forcing us into manual intervention situations.
8 > Mostly on systems with LVM.
9 >
10 > > I don't exactly know what your situation is, but as I said, this
11 > > proposal wouldn't affect your systems. I'm not talking about lastrites
12 > > for eudev, just making it the default for new installs.
13
14 It would affect new installations.  But yes, we can switch it back to
15 eudev post install.
16
17 >
18 > I'm completely against the proposal.
19 >
20 > >>>> I would want some convincing that it was not another step on the road
21 > >>>> to Gentoo being assimilated by systemd.
22 > >>>>
23 > >>>> We had this discussion several years ago when the default became
24 > >>>> eudev. What's changed?
25 > >>>
26 > >>> If systemd folks do make udev inseparable from systemd, then we would
27 > >>> need eudev to be the default, but as I see it right now, there is not
28 > >>> a case for it being the default.
29 >
30 > Other than that it works and the systemd version does not.  Might be
31 > configuration dependent, but I don't expect a default udev
32 > configuration/system side to not cause LVM breakages when running
33 > commands as simple as "lvs".  eudev in coparison just works.
34 >
35 > >  I don't know what is going on with your systems, but I suspect possible
36 > >  configuration dependence.
37
38 Ok, simplest mechanism we've found:
39
40 Install a system with at least one LV partition and leave some space
41 available in the VG, then do:
42
43 term 1:  watch lvs
44
45 term 2:  while true; do lvcreate -L1G -s -ntemp_snap /dev/${vg}/${lv} &&
46 lvremove /dev/${vg}/temp_snap; done
47
48 Give it anywhere from two two five minutes.  Can be hours sometimes. 
49 But eventually it does die.  Can't say the same for eudev.
50
51 >
52 > > When are the breakages happening-- just at random or during bootup?
53
54 In some cases rebooting is the only way to recover.
55
56 Kind Regards,
57 Jaco
58
59 -----BEGIN PGP SIGNATURE-----
60
61 iQEzBAEBCAAdFiEEyyCUcKjG7P5BDam8CC3Esa/37p4FAl8vJyEACgkQCC3Esa/3
62 7p4eewf/bOXgnx4n30HUZnTmvhyjC4F2MTc8bOwYj45t+UMeGoIN8C+GMHxWMGvG
63 NQpoK2hkY8egykCbuO4rSBwV9YS/naAiAZEcEXCPdcAUgV2FxJSGWKCLDLfTiflg
64 vXCLpd8ybxVbVhEO5XU8K4jTc9fc4peY/4ZVK0Lhl80rzWLf/yrc9+IurBZE+0g0
65 GXpHxNa6e2AZWPFyNXMu83fatlyOZpy/WXE7owb+yLPwTJPs30W9OLFQ6lWXSLdx
66 FGyLBh8vFn9BExF3IS1ZgKYIBRrH45AazMNV3+fvO+aZX/6UfXDID/JDjXHdq3bl
67 awMSVX40kYbgskCkOwf5DreCrs7nBw==
68 =ROIf
69 -----END PGP SIGNATURE-----