Re: [PATCH] cfq + io priorities

[Guillaume Chazarain <guichaz@yahoo.fr>]

> A process has an assigned io nice level, anywhere from 0 to 20. Both of

OK, I ask THE question : why not using the normal nice level, via
current->static_prio ?
This way, cdrecord would be RT even in IO, and nice -19 updatedb would have
a minimal impact on the system.

> these end values are "special" - 0 means the process is only allowed to
> do io if the disk is idle, and 20 means the process io is considered

So a process with ioprio == 0 can be forever starved. As it's not
done this way for nice -19 tasks (unlike FreeBSD), wouldn't it be
safer to give a very long deadline to ioprio == 0 requests ?


Thanks for making something I have been dreaming of for a long time :)


Guillaume