mtdblock caching and syncing
jamie at shareable.org
Thu Apr 9 14:07:24 EDT 2009
Doug Graham wrote:
> > The device in question isn't the flash. It's the mtdblock device. So
> > fsync semantics are preserved. This is the same as writing to a file
> > on a hard drive, calling fsync, and having it sit in the hard drive's
> > cache.
> That's a good point, and one I've wondered about before. I don't know
> much about how hard drives manage their cache, but I would assume that
> they don't leave dirty data in their cache for an unbounded period
> of time. I'd guess that data is written to the actual disk within a
> few 10s of milliseconds after being sent to the device.
Ideally, fsync() should flush data from a hard drive's cache too.
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