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by X-Istence 2595 days ago
Some of the backports aren't nearly as fast or performant as using a newer kernel though.

For example eBPF was back ported (and also in CentOS), but running a syscall heavy work-load in a docker container on the older kernel about 50% of the CPU time was spent in the kernel filter.

I ended up moving our entire CI/CD platform to Ubuntu 18.04 and the performance issues went away and my workloads now run at full speed without slowdowns.

RHEL 8 comes with the 4.18 series of the Linux kernel that is already EOL. That's a shame and once again it will fall behind quickly :/
2 comments
CameronNemo 2595 days ago
Seriously why did they not up it to 4.19? Do they hate bicycles? Do they make money based on the fact that upstream LTS kernels have short shelf lives compared to RHEL's own LTS kernels?
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rwmj 2595 days ago
The kernel version was finalized some time before this release when 4.18 was current. Red Hat expends a ton of effort on long term maintenance and huge backports of new features to the kernel, so while I don't want to speak for the kernel team, I don't think the upstream stable kernels bring very much to the table.

Plus (my personal view) what goes into the upstream stable kernel is fairly random based on just mailing list NACKs, whereas what goes into the RH kernel has to pass a massive range of automated tests on a wide variety of real hardware.

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snuxoll 2593 days ago
Red Hat also certifies a whitelist of symbols that will remain identical in all future releases for the life cycle, stuff like that takes time so just grabbing the newest LTS kernel the moment they cut a release isn’t feasible.
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paulcarroty 2595 days ago
> That's a shame and once again it will fall behind quickly

RH use kernel with TONS of patches, so, version isn't critical here.

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pas 2595 days ago
Their frankenkernel is very hit and miss, backports or not. Docker had to disable a few features, because at first they seemed to work, but then they were buggy on RHEL.
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Spivak 2595 days ago
But why wouldn't you use Red Hat's build of Docker? I mean if you're already paying them...
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paulcarroty 2594 days ago
Can't remember any real problems with docker on RHEL/Fedora.
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X-Istence 2594 days ago
I mentioned my sys call filtering issue with eBPF taking up massive amounts of CPU time...
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