Messages in this thread | | | Date | Mon, 22 Sep 2014 13:02:03 -0400 | Subject | Re: [RFC PATCH 0/7] Non-blockling buffered fs read (page cache only) | From | Milosz Tanski <> |
| |
I'll send out the next RFC with 2 syscalls and magic position values. I'm waiting for Jeff to chime in on the v2 patchset before I send out the next one.
On Mon, Sep 22, 2014 at 12:42 PM, Christoph Hellwig <hch@infradead.org> wrote: > On Mon, Sep 22, 2014 at 12:32:02PM -0400, Milosz Tanski wrote: >> I spent some time thinking about multi-position scatter/gather in >> context of this over the weekend. The non-blocking case seams easy, >> the implementation I purposed needs an extra loop. Where this gets >> hairy is making the non-trivial blocking case work well (as in have >> concurrent requests for each of the ranges) in the filesystem code. If >> that's the road we're going to go down I have a gut feeling we're >> going to get stuck in the same spot(s) as the other non-blocking >> buffered r/w attempts from the past. > > The other thing sis that we have a basically ready, easy to use > implementation of flagged I/O (my name for the new syscalls), while > S/G I/O will take forever to discuss and is the natual vehicle for > other extensions like T10 DIX. > > I'd like to suggest you consolidate your syscalls down from 4 to 2 > as suggestes by overloading the negative offset argument, giving > us two more syscalls slows for S/G once it's ready. Note that > a sync S/G syscalls should of course also support these flags, although > I suspect the primary use cases for S/G I/O would be through the aio > machinery.
-- Milosz Tanski CTO 16 East 34th Street, 15th floor New York, NY 10016
p: 646-253-9055 e: milosz@adfin.com
| |