Re: Mysterious CFQ crash and RCU

Paul Bolle
2011-05-25T09:40:27Z

On Wed, 2011-05-25 at 11:30 +0200, Jens Axboe wrote:
> If you build CFQ modular, then all you have to do is switch to using CFQ
> before starting your testing:
>
> # echo cfq > /sys/block/sda/queue/scheduler
>
> and switch sda to eg noop before you can remove cfq-iosched again. As
> long as things crash, then you wont be able to remove cfq anyway and you
> have to reboot to test something new anyway. So the modular nature of
> cfq-iosched may not help you all that much in the end.

The main advantage I hope for is to reduce build and install time (it's
much quicker to rebuild a module, copy it into /lib/modules, perhaps
upgrade the initramfs, etc., than it is to rebuild an entire kernel, all
its modules, etc.).

Paul