Messages in this thread | | | Date | Fri, 06 Sep 2002 08:47:38 +0200 | From | Helge Hafting <> | Subject | Re: One more bio for for floppy users in 2.5.33.. |
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Linus Torvalds wrote: [...] > I do think we might make the read-ahead window configurable, and make slow > devices have slightly smaller windows. > > On the other hand, I don't think the 64kB IO actually _hurts_ per se, as > long as it doesn't delay the stuff we care about.
I can think of one case where large readahead hurts for floppy, even with partial completion:
1. Grab a stack of floppies 2. Try mounting (or mount+ls) one after another, in search of the right one.
You'll get the results on screen fast enough (mount succeeded/failed or ls showed the right/wrong files) but when it is the wrong floppy you have to wait for several tracks to read before you may eject and try the next one.
Sure, it is only reading so ejecting "by force" won't hurt the fs but then you have to wait on io errors instead.
So I think a smaller readahead might make sense for floppies, unless people don't do this sort of search anymore. I don't.
Helge Hafting - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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