[Pkg-xen-devel] [admin] [Xen-devel] [BUG] task jbd2/xvda4-8:174 blocked for more than 120 seconds.

[Samuel Thibault]

Hello,

Hans van Kranenburg, le sam. 09 févr. 2019 17:01:55 +0100, a ecrit:
> > I have forwarded the original mail: all VM I/O get stuck, and thus the
> > VM becomes unusable.
> 
> These are in many cases the symptoms of running out of "grant frames".

Oh!  That could be it indeed.  I'm wondering what could be monopolizing
them, though, and why +deb9u11 is affected while +deb9u10 is not.  I'm
afraid increasing the gnttab max size to 32 might just defer filling it
up.

>   -# ./xen-diag  gnttab_query_size 5
>   domid=5: nr_frames=11, max_nr_frames=32

The current value is 31 over max 32 indeed.

> With Xen 4.8, you can add gnttab_max_frames=64 (or another number, but
> higher than the default 32) to the xen hypervisor command line and reboot.

admin@: I made the modification in the grub config. We can probably try
to reboot with the newer hypervisor, and monitor that value.

Samuel