On středa 25. května 2016 2:08 Richard Brown wrote:
But I am certain that choosing 4.4 sets us in a very good foundation for the future. Being an LTS kernel means we can be certain it will be well supported for the full lifespan of 42.2 and, if we choose to not do a kernel upgrade in 42.3, then we know that we still be on a very well supported, stable, LTS kernel.
IMHO the way more important point is it's going to be backed up by SLE maintenance process which is quite a big difference from openSUSE one.
Let's take a look at some numbers for recent/current openSUSE kernel branches. Column "stable" shows number of commit id's inherited from (upstream) stable-x.y updates, column "fixes" number of patches in patches.fixes/ (which are supposed to be bugfixes), "sum" is the sum of these two. The metric is far from perfect but it gives some picture:
branch based on stable fixes sum ------------------------------------------------------------ openSUSE-13.1 (3.11) 665 259 924 openSUSE-13.2 (3.16) 856 187 1043 openSUSE-42.1 (4.1 - LTS) 2473 70 2543 evergreen-11.4 (3.0 / SLE11-SP2) 3778 942 4720 evergreen-13.1 (3.12 / SLE12-SP1) 6208 932 7140 openSUSE-42.2 (4.4 / SLE12-SP2) 1451 257 1708
First obvious observation is the big difference between the first two (backed by neither upstream LTS nor SLE) and the rest. But it's also apparent that relying only on upstream LTS releases would result in missing a substantial number of bugfixes which were never included in them. After all, these days one can say almost every kernel version has an LTS process of some kind (e.g. out of the 13 versions from 3.12 to 4.4, only 4 do not). SLE maintenance is much more rare.
Also, with openSUSE kernel being essentially a SLE one, most openSUSE kernel bugs are going to affect SLE as well which can help get kernel developers' attention to them. After all, we already had three bugs affecting SLE12-SP1 which were first found on Evergreen 13.1. With larger Leap 42.2 user base and 42.2 going to be officially supported, this synergy effect is IMHO going to be much stronger.
And I guess that's my point, right now, based on the information we have and the points raised to date, I am utterly convinced that the SLE 12 SP2 Kernel (4.4 with whatever backports are already there) is the correct choice for Leap 42.2
Agreed. Throwing away the openSUSE-SLE synergy just to get higher version number would be irresponsible, IMHO. After all, there is still the option to run TW kernel on Leap for those who need support for some new hardware but are not adventurous enough to go full Tumbleweed.