MGLRU Patches Merged To "mm-stable" Ahead Of Linux 6.1 - New Benchmarks Look Good

As further indication of MGLRU hopefully being mainlined for Linux 6.1 as planned, the Multi-Gen LRU patches have now been moved to Andrew Morton's mm-stable branch.

MGLRU has been undergoing rigorous testing via Andrew Morton's mm-unstable branch and by the many parties involved with MGLRU and the various downstream kernel flavors already shipping this feature to address the Linux kernel's poor existing page reclamation code. MGLRU has shown to help Linux performance especially in memory pressure / low RAM situations and has been a big win already for Chrome OS and Android devices, among others.

MGLRU has been looking to be one of the best mainline kernel innovations of 2022, assuming it does indeed land successfully with the Linux 6.1 merge window opening up in early October.

Those wanting to give the latest MGLRU code a whirl can find the latest patches now via akpm/mm.git's mm-stable branch.

Recently I fired up some MGLRU on/off benchmarks of the v15 patches using an AMD Ryzen 5 5500U system with just 8GB of RAM.








For that modest hardware with just 8GB of RAM, having MGLRU enabled dramatically increased the PostgreSQL server performance... Good news for containers, SOHO servers running database workloads, small development/testing boxes, etc. PostgreSQL saw the most significant improvements with the MGLRU-enabled kernel.

RocksDB also saw a big uplift.

The Natron renderer seemed to benefit too. There were some cases of minor (usually a few percent or less) performance regressions with MGLRU enabled to be investigated. If/when MGLRU is picked up for Linux 6.1 I'll be around with a whole lot more benchmarking on different systems.