[Gluster-devel] how does meta xlator work?

Emmanuel Dreyfus manu at netbsd.org
Tue Aug 12 01:04:01 UTC 2014


Anand Avati <avati at gluster.org> wrote:

> So my guess would be to inspect how direct_io_mode works in those FUSE
> implementations first. It is unlikely to be any other issue.

Indeed this is the problem: the kernel open and close the file without
sending any read request. 

But there is something I don't get withthe fix: 
- the code forces direct IO if (state->flags & O_ACCMODE) != O_RDONLY),
but here the file is open read/only, hence I would expect fuse xlator to
do nothing special
- using direct IO is the kernel's decision, reflecting the flags used by
calling process on open(2). How can the fuse xlator convince the kernel
to enable it?

-- 
Emmanuel Dreyfus
http://hcpnet.free.fr/pubz
manu at netbsd.org


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