Re: [PATCH v6 0/9] Multigenerational LRU Framework

From: Sofia Trinh
Date: Wed Jan 12 2022 - 01:07:37 EST


On Tue, Jan 11, 2022 at 12:41 AM Yu Zhao <yuzhao@xxxxxxxxxx> wrote:
>
> On Tue, Jan 04, 2022 at 01:30:00PM -0700, Yu Zhao wrote:
> > On Tue, Jan 04, 2022 at 01:22:19PM -0700, Yu Zhao wrote:
> > > TLDR
> > > ====
> > > The current page reclaim is too expensive in terms of CPU usage and it
> > > often makes poor choices about what to evict. This patchset offers an
> > > alternative solution that is performant, versatile and
> > > straightforward.
> >
> > <snipped>
> >
> > > Summery
> > > =======
> > > The facts are:
> > > 1. The independent lab results and the real-world applications
> > > indicate substantial improvements; there are no known regressions.
> > > 2. Thrashing prevention, working set estimation and proactive reclaim
> > > work out of the box; there are no equivalent solutions.
> > > 3. There is a lot of new code; nobody has demonstrated smaller changes
> > > with similar effects.
> > >
> > > Our options, accordingly, are:
> > > 1. Given the amount of evidence, the reported improvements will likely
> > > materialize for a wide range of workloads.
> > > 2. Gauging the interest from the past discussions [14][15][16], the
> > > new features will likely be put to use for both personal computers
> > > and data centers.
> > > 3. Based on Google's track record, the new code will likely be well
> > > maintained in the long term. It'd be more difficult if not
> > > impossible to achieve similar effects on top of the existing
> > > design.
> >
> > Hi Andrew, Linus,
> >
> > Can you please take a look at this patchset and let me know if it's
> > 5.17 material?
> >
> > My goal is to get it merged asap so that users can reap the benefits
> > and I can push the sequels. Please examine the data provided -- I
> > think the unprecedented coverage and the magnitude of the improvements
> > warrant a green light.
>
> Downstream kernel maintainers who have been carrying MGLRU for more than
> 3 versions, can you please provide your Acked-by tags?
>
> Having this patchset in the mainline will make your job easier :)
>
> Alexandre - the XanMod Kernel maintainer
> https://xanmod.org
>
> Brian - the Chrome OS kernel memory maintainer
> https://www.chromium.org
>
> Jan - the Arch Linux Zen kernel maintainer
> https://archlinux.org
>
> Steven - the Liquorix kernel maintainer
> https://liquorix.net
>
> Suleiman - the ARCVM (Android downstream) kernel memory maintainer
> https://chromium.googlesource.com/chromiumos/third_party/kernel
>
> Also my gratitude to those who have helped test MGLRU:
>
> Daniel - researcher at Michigan Tech
> benchmarked memcached
>
> Holger - who has been testing/patching/contributing to various
> subsystems since ~2008
>
> Shuang - researcher at University of Rochester
> benchmarked fio and provided a report
>
> Sofia - EDI https://www.edi.works
> benchmarked the top eight memory hogs and provided reports

Tested-by: Sofia Trinh <sofia.trinh@edi.works>