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

From: David Rientjes
Date: Wed Jun 03 2020 - 15:27:11 EST


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.