LKML News v5.12-rc7

[RFC PATCH v1 00/11] Manage the top tier memory in a tiered memory (Tim Chen)

https://lkml.kernel.org/r/cover.1617642417.git.tim.c.chen@linux.intel.com

There are two patchsets for better handling of tiered-memory. [PATCH 00/10] [v7] Migrate Pages in lieu of discard (https://lore.kernel.org/linux-mm/20210401183216.443C4443@viggo.jf.intel.com/) makes cold pages to be placed in PMEM instead of DRAM, and [PATCH 0/6] [RFC v6] NUMA balancing: optimize memory placement for memory tiering system (https://lore.kernel.org/linux-mm/20210311081821.138467-1-ying.huang@intel.com/) allows hot pages to be placed in DRAM instead of PMEM.

This patchset further improves the situation, by providing memory monitors on the top tier memory that each cgroup is using, and enables kswapd to demote top tier memory from cgroups when excess top tier memory usage is observed. In other words, this allows provisioning of different amount of top tier memory for each cgroup, depending on each cgroup’s needs.

[PATCH v7 00/28] Memory Folios (Matthew Wilcox)

https://lkml.kernel.org/r/20210409185105.188284-1-willy@infradead.org

Seventh version of the page folio patchset. It makes THP handling simpler.

Linux 5.12-rc7 (Linus Torvalds)

https://lkml.kernel.org/r/CAHk-=wiHGchP=V=a4DbDN+imjGEc=2nvuLQVoeNXNxjpU1T8pg@mail.gmail.com

Unlike the sixth rc, which shrinked as expected, this time it became bigger than usual. It’s biggest rc7 for 5.x series. Torvalds says it’s due to the networking fixes that didn’t arrive in last release but this release. So we will see rc8 next week unless the it is calm enough like dead.

Below is the diffstat of the releases in the last two years.

Note that the y-axis is in logarithm. I draw it using https://github.com/sjp38/relstat and https://github.com/sjp38/lazybox using below command:

$ relstat.py --since 2019-03-29 | ~/lazybox/gnuplot/plot.py \
    --data_fmt table --type labeled-lines --xtics_rotate -90 \
    --font "Times New Roman, 5pt" --ylog --pointsize 0.3

And, below is the diffstat of the -rc5 releases in the last two years.