Re: [PATCH] mm: thp: Add new kernel parameters transparent_hugepage_defrag/khugepaged_defrag

[Gavin Guo]

On Thu, Jun 4, 2020 at 3:27 AM David Rientjes <rientjes@xxxxxxxxxx> wrote:
>
> On Wed, 3 Jun 2020, Vlastimil Babka wrote:
>
> > > There is no way to set up the defrag options in boot time. And it's
> > > useful to set it up by default instead of making it work by a
> > > systemd/upstart service or put the command to set up defrag inside
> > > /etc/rc.local.
> > >
> > > Signed-off-by: Gavin Guo <gavin.guo@xxxxxxxxxxxxx>
> >
> > Well, maybe isntead of adding these handlers, we could extend the new boot
> > parameter sysctl support (handling procfs /proc/sys/) to sysfs (/sys) as well,
> > as Eric already suggested? [1]
> >
> > [1] https://lore.kernel.org/linux-api/87bloj2skm.fsf@xxxxxxxxxxxxxxxxxxxxx/
> >
>
> Fully agreed, I think the solution needs to be more generic since thp
> defrag isn't special here.  With the generic support to tune sysctls and
> sysfs tunables from the command line it seems like this patch would be
> redundant.

Agreed, I'll try to investigate more on how to do that in a generic way.