> Am 05.02.2015 um 14:25 schrieb Till Oliver Knoll
> <[email protected]>:
>
> ...
>
> Does it make sense to guarantee/enforce "sequential (exclusive) access to the
> harddisk" on application level, or would I re-invent functionality already
> present in the underlying OS/disk driver (and maybe even sacrifice
> performance)?
I eventually found a link which seems to confirm that it would be best to only
have sequential read/write access with physically spinning drives, that is,
have some kind of "IO Manager" in the application:
http://www.tomshardware.co.uk/forum/251768-32-impact-concurrent-speed
Off course the tricky part then is that the Writer thread does not block the
Reader thread for too long, such that the Work Queue would become empty (and
the worker threads would be sitting there "idle").
Likewise the Writer thread must have enough chances to write, such that the
Result Queue becomes not too large ("memory constraints"). Probably some kind
of priorisation scheme taking Queue counts into consideration is the answer -
but not part of my question; I am really just interested in whether concurrent
read/write access should be avoided in the first place these days (or not).
For SSDs it still might be okay (or even better?) to use concurrent read/write
access?
Any other thoughts on that?
Thanks,
Oliver_______________________________________________
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