kvm vs firefox issue?

[Eyal Lebedinsky]

I am running up-to-date f36.

Recently I had kvm "virsh restore" take a long time. Normally it takes less than
10s but now it took 10-15m!.
Then it took 30m (qemu-system-x86_64 running 100% CPU all the time) and I started looking
around.
I noticed that khugepaged is also running 100% CPU. Thinking that there may be a memory
issue, on a whim, I closed firefox. KVM came up immediately.
The machine has enough memory (32GB) and kvm was allocated 8GB.

Right now I again resumed the vm, and after 2m I closed firefox and again kvm responded
instantly.

This started only recently (kernel 6.0.18 or 6.1, or another update?)

Is there a known problem.

-- 
Eyal Lebedinsky (fedora(a)eyal.emu.id.au)

[Ron Yorston]

Eyal Lebedinsky <fedora(a)eyal.emu.id.au&gt; wrote:
> This started only recently (kernel 6.0.18 or 6.1, or another update?)
>
> Is there a known problem. 
There is.  It's in the 6.1 kernel and it isn't yet fixed in Fedora.
(Not even in the 6.1.8 kernel currently in testing.)

Here's a SuSE bug report:

   https://bugzilla.suse.com/show_bug.cgi?id=1206848

which suggests:

   echo never > /sys/kernel/mm/transparent_hugepage/enabled

as a workaround until new kernels are available.  I've confirmed
that this seems to work with a Fedora 6.1 kernel.

Cheers,

Ron

[Go Canes]

On Thu, Jan 26, 2023 at 7:04 AM Ron Yorston <rmy(a)frippery.org&gt; wrote:
>  Eyal Lebedinsky <fedora(a)eyal.emu.id.au&gt; wrote:
>  >This started only recently (kernel 6.0.18 or 6.1, or another update?)
>  >
>  >Is there a known problem.
>
>  There is.  It's in the 6.1 kernel and it isn't yet fixed in Fedora.
>  (Not even in the 6.1.8 kernel currently in testing.)
>
>  Here's a SuSE bug report:
>
>     https://bugzilla.suse.com/show_bug.cgi?id=1206848
>
>  which suggests:
>
>     echo never > /sys/kernel/mm/transparent_hugepage/enabled
>
>  as a workaround until new kernels are available.  I've confirmed
>  that this seems to work with a Fedora 6.1 kernel. 
I have been seeing an issue where my Windows VM appears to hang during
boot - I've been working around it by rebooting and running the VM
without anything else started.  I haven't had time to investigate, but
checked today based on this thread and can confirm that I am seeing
the same thing.  And it isn't just Firefox - before my VM would start
running normally I had to shut everything down including the duplicati
service (used for backups).

[Go Canes]

On Thu, Jan 26, 2023 at 4:58 PM Go Canes <letsgonhlcanes0(a)gmail.com&gt; wrote:
>  On Thu, Jan 26, 2023 at 7:04 AM Ron Yorston <rmy(a)frippery.org&gt; wrote:
>  >
>  > Eyal Lebedinsky <fedora(a)eyal.emu.id.au&gt; wrote:
>  > >This started only recently (kernel 6.0.18 or 6.1, or another update?)
>  > >
>  > >Is there a known problem.
>  >
>  > There is.  It's in the 6.1 kernel and it isn't yet fixed in Fedora.
>  > (Not even in the 6.1.8 kernel currently in testing.)
>  >
>  > Here's a SuSE bug report:
>  >
>  >    https://bugzilla.suse.com/show_bug.cgi?id=1206848
>  >
>  > which suggests:
>  >
>  >    echo never > /sys/kernel/mm/transparent_hugepage/enabled
>  >
>  > as a workaround until new kernels are available.  I've confirmed
>  > that this seems to work with a Fedora 6.1 kernel.
>
>  I have been seeing an issue where my Windows VM appears to hang during
>  boot - I've been working around it by rebooting and running the VM
>  without anything else started.  I haven't had time to investigate, but
>  checked today based on this thread and can confirm that I am seeing
>  the same thing.  And it isn't just Firefox - before my VM would start
>  running normally I had to shut everything down including the duplicati
>  service (used for backups). 
I can confirm that I no longer see the issue with kernel 6.1.10-100.fc36.x86_64.

[Eyal Lebedinsky]

Thanks Ron,

On 26/01/2023 23.04, Ron Yorston wrote:
>  Eyal Lebedinsky <fedora(a)eyal.emu.id.au&gt; wrote:
> > This started only recently (kernel 6.0.18 or 6.1, or another update?)
> >
> > Is there a known problem.
>  
>  There is.  It's in the 6.1 kernel and it isn't yet fixed in Fedora.
>  (Not even in the 6.1.8 kernel currently in testing.)
>  
>  Here's a SuSE bug report:
>  
>      https://bugzilla.suse.com/show_bug.cgi?id=1206848
>  
>  which suggests:
>  
>      echo never > /sys/kernel/mm/transparent_hugepage/enabled
>  
>  as a workaround until new kernels are available.  I've confirmed
>  that this seems to work with a Fedora 6.1 kernel. 
Seems to work for me too. Now added to rc.local.

Eyal

>  Cheers,
>  
>  Ron 
-- 
Eyal Lebedinsky (fedora(a)eyal.emu.id.au)