Badrinath Venkatachari wrote:
>
> Hi,
> I am trying to understand the I/O scheduling under linux.
>
> I believe linux right now implements the elevator algorithm in only one
> direction...(CSCAN). Would it be possible to implement elevator in both
> directions ??
>
> Also, I was trying to modify the scheduling algorithm slightly by
> redirecting the requests to a function that I wrote to sequence the
> requests based on some priority. To periodically move the requests from my
> Q to the linux Q I need to have a timer-based thread that does
> it (basically issues make_requests periodically for each request
> in the Q I maintain). However, I am not sure about how I can initialize
> this thread before any I/O can be handled...
>
> please help.....anyone.
>
> thanks a lot in advance.
>
> badri
>
> -
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Elevators are more efficient if they go in one direction. Disk spin direction
is one reason, another is that when you reach the end of the disk the density of
unsatisfied requests is greater at the beginning of the disk.
Hans
-- You can get ReiserFS at http://devlinux.org/namesys, and customizations and industrial grade support at reiser@idiom.com.- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
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