Re: [[PATCH]] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged

[Vijay Balakrishna]

On 9/10/2020 3:01 PM, Kirill A. Shutemov wrote:
> On Thu, Sep 10, 2020 at 01:47:39PM -0700, Vijay Balakrishna wrote:
> > When memory is hotplug added or removed the min_free_kbytes must be
> > recalculated based on what is expected by khugepaged.  Currently
> > after hotplug, min_free_kbytes will be set to a lower default and higher
> > default set when THP enabled is lost. This leaves the system with small
> > min_free_kbytes which isn't suitable for systems especially with network
> > intensive loads.  Typical failure symptoms include HW WATCHDOG reset,
> > soft lockup hang notices, NETDEVICE WATCHDOG timeouts, and OOM process
> > kills.
> >
> > Fixes: f000565adb77 ("thp: set recommended min free kbytes")
> >
> > Signed-off-by: Vijay Balakrishna <vijayb@xxxxxxxxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
>
> NAK. It would override min_free_kbytes set by user.

Hi Kirill,

To fix the issue you raised I just submitted
https://lore.kernel.org/lkml/1600145748-26518-1-git-send-email-vijayb@xxxxxxxxxxxxxxxxxxx/

Thanks,
Vijay

>