Shutdown

[Norman Feske]

Hi Colin,

> 1) I have been using Sculpt on real hardware. What I do for shutdown is
> to open "Storage" under "Components" and de-select "Use" on my primary
> "GENODE*" partition. I assumed that this would cause any pending file
> operations to complete, similar to a UNIX "sudo umount". Is that right?

Unfortunately not. By "unusing" the Sculpt partition, you are
immediately wiping out all components without mercy. You probably have
been lucky because the file-system's cache is quite small and the file
system writes back data periodically.

> 2) Sometimes I do feel the need to reboot Sculpt, but potentially this
> is not completely necessary if there were a way to restart certain
> services. Is it possible to restart internal components? Most common
> culprits for me would be usb_drv, and the depot-related components.
> Ideally this could be done without the runtime system killing my VMs,
> but I suspect that's asking too much.

The USB driver and the depot components are strict dependencies. If
restarted, a dependent VM would be implicitly restarted as well. For
example, even though you can in fact force the restart of the USB driver
by editing a 'version' attribute in USB driver's <start> node in
/config/drivers, this is not helpful because all dependent components
(including Sculpt's leitzentrale) would be affected. Better don't do
this! ;-)

We actually plan to make drivers for network, wifi, framebuffer, and
audio restartable, which will generally become possible because those
particular drivers do not encapsulate much state. But bus drivers (like
USB) or storage drivers contain complex state that would go lost upon
restart. So those components must ultimately become infallible.

You can help us with that. I encourage you to report any problems that
you experience with those low-level components, if possible.

Cheers
Norman

-- 
Dr.-Ing. Norman Feske
Genode Labs

https://www.genode-labs.com · https://genode.org

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Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth