[mdlug] Linux Kernel 6.1

[LAP]

To those of you, like me, who compiles his own kernel there
are some interesting changes in the latest 6.1 release.  Usually --
for me anyway -- a new kernel doesn't seem to differ much from
the previous versions but not this time.

Doing the usual "make oldconfig" the first noteworthy feature
that appears is:

 Multi-Gen LRU (LRU_GEN) [N/y/?] (NEW)

Multi-Gen LRU is a new high-performance memory management
implementation that is intended to replace the old one.

But it is not enabled by default and so I enabled it.

Next along was this:

 NR_CPUS is set to an actual number of CPUs (FORCE_NR_CPUS) [N/y/?] (NEW)

I had to do some checking and I found that the usual .config
entry for NR_CPUS involves a range, with the default being 64:

CONFIG_NR_CPUS_RANGE_BEGIN=2
CONFIG_NR_CPUS_RANGE_END=512
CONFIG_NR_CPUS_DEFAULT=64

Supposedly, forcing the NR_CPUS to be a specific value will allow
optimization of kernel routines.

https://www.spinics.net/lists/kernel/msg4493525.html

More optimization, in my assessment is always better and so I enabled
this option as well.

Ideally, every Linux user should at least build his own kernel.  The
distros can only offer a generic, lowest-common-denominator type product.