Page 1 of 1

LM 19 and Kernels

Posted: Mon Aug 20, 2018 6:02 am
by Kabé
Hi all,

Recently, I installed linux mint 19 (Mate) on both my laptop and my desktop (after having good expériences since LM 17).
It works perfectly well, but both had a longer boot time, especially a long delay between the BIOS (or manufacturer's) splash screen and the LM splash screen (30s instead of about 15s before).
Now, I may not be a newbie, but neither a linux savvy. I tried some changes in the GRUB menu, to no avail, and since LM 19 or the 4.15 kernel seems to provoke similar problems with others, I tried upgrading and downgrading the Kernel (and discovered UKUU at the same time, since these other Kernels don't show up in the Mint update manager). This helped, with both 4.14.133 (on my older desktop, which I assembled myself) and 4.17.15 (on my Dell XPS 13).

Now, my solution may not be the most elegant, and it fixed something that was not really a problem (since both machines worked perfecly well after boot-up), but a mere annoyance), what are your thoughts on the 4.15 Kernel and trying other Kernels on LM 19 ? My rather uninformed impression, based on the above experience and the messages in this forum about boot problems, is that the 4.15 Kernel may not be the most reliable...

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 6:08 am
by catweazel
Kabé wrote: Mon Aug 20, 2018 6:02 am I tried upgrading and downgrading the Kernel (and discovered UKUU at the same time, since these other Kernels don't show up in the Mint update manager). This helped, with both 4.14.133 (on my older desktop, which I assembled myself) and 4.17.15 (on my Dell XPS 13).

Now, my solution may not be the most elegant...
Don't try this at home, folks. This is absolutely not tested or supported. If things take a turn for the worst you are expected to be knowledgable enough to repair your system on your own.

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 6:29 am
by Kabé
Sorry, I should have started with this kind of warning, indeed. I probably too easily assumed that people will not try this when they don't know how to turn it back...
But, do you have thoughts on these LM 19/Kernel combinations?

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 6:31 am
by catweazel
Kabé wrote: Mon Aug 20, 2018 6:29 am But, do you have thoughts on these LM 19/Kernel combinations?
Yes, and you just read them up there.

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 6:35 am
by Pjotr
catweazel wrote: Mon Aug 20, 2018 6:31 am
Kabé wrote: Mon Aug 20, 2018 6:29 am But, do you have thoughts on these LM 19/Kernel combinations?
Yes, and you just read them up there.
+1

From the official Ubuntu wiki:
By default, Ubuntu systems run with the Ubuntu kernels provided by the Ubuntu repositories. However it is handy to be able to test with unmodified upstream kernels to help locate problems in Ubuntu kernel patches, or to confirm that upstream has fixed a specific issue. To this end we now offer select upstream kernel builds. These kernels are made from unmodified kernel source but using the Ubuntu kernel configuration files. These are then packaged as Ubuntu .deb files for simple installation, saving you the time of compiling kernels, and debugging build issues.

These kernels are not supported and are not appropriate for production use.
Source: https://wiki.ubuntu.com/Kernel/MainlineBuilds

As an aside: kernel 4.15.x works fine on all of my Mint 19 machines.

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 1:41 pm
by 151tom
.

Re: LM 19 and Kernels

Posted: Mon Aug 20, 2018 2:22 pm
by gm10
Kabé wrote: Mon Aug 20, 2018 6:29 am But, do you have thoughts on these LM 19/Kernel combinations?
Nothing wrong with them as long as you understand the implications. Mainline kernels are more bare-bones than the Ubuntu version, which is in part also why they are expected to boot slightly faster. For the fastest possible kernel load you'd actually compile the kernel yourself, stripping out all drivers you don't need.

I wouldn't run mainline kernels just for boot times though. Ubuntu runs every kernel through a bunch of compatibility and regression tests. As we know they don't catch every problem, but they do try. That's why I would suggest that, if you have found that the 4.17 series runs better on your system, to use the 4.17 kernels from Ubuntu's cosmic repository instead: https://packages.ubuntu.com/cosmic/linux-image-generic. Those will be the default kernel for Ubuntu's upcoming fall release.