Re: [RESEND][RFC] BFQ I/O Scheduler

[Pavel Machek <pavel@ucw.cz>]

On Tue 2008-04-01 17:29:03, Fabio Checconi wrote:
> [sorry for reposting, wrong subject]
> 
> Hi,
>     we are working to a new I/O scheduler based on CFQ, aiming at
> improved predictability and fairness of the service, while maintaining
> the high throughput it already provides.
> 
> The patchset, too big for lkml posting, is available here:
>     http://feanor.sssup.it/~fabio/linux/bfq/patches/
> 
> The Budget Fair Queueing (BFQ) scheduler turns the CFQ Round-Robin
> scheduling policy of time slices into a fair queueing scheduling
> of sector budgets.  More precisely, each task is assigned a budget
> measured in number of sectors instead of amount of time, and budgets
...
> In the first type of tests, to achieve a higher throughput than CFQ
> (with the default 100 ms time slice), the maximum budget for BFQ
> had to be set to at least 4k sectors.  Using the same value for the

Hmm, 4k sectors is ~40 seconds worst case, no? That's quite long...
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