Re: mlockall(MCL_CURRENT) blocking infinitely

[Robert Stupp]

On Wed, 2019-11-06 at 18:25 +0100, Jan Kara wrote:
> On Wed 06-11-19 18:03:10, Robert Stupp wrote:
> > Oh, and I just realized, that I have two custom settings in my
> > /etc/rc.local - guess, I configured that when I installed that
> > machine
> > years ago. Sorry, that I haven't mentioned that earlier.
> >
> > echo 0 > /sys/block/nvme0n1/queue/read_ahead_kb
> > echo never >
> > /sys/kernel/mm/transparent_hugepage/defrag
> >
> > That setting is probably not quite standard, but I assume there are
> > some database server setups out there, that set RA=0 as well.
>
> Ok, yes, that explains ra_pages == 0. Thanks for the details.

Ah! And with these settings, a fresh & clean installation of Ubuntu
eoan (5.3.x kernel), hangs during reboot.
And if the VM's booted with these settings in /etc/rc.local, the
mlockall(MCL_CURRENT) is reproducible as well.