LFCS: Preparing Linux for nonvolatile memory devices

There may be actually no case for redesigning current APIs, because they provide a logical view of devices that is quite independent of the underlying technology, and that independence is well woth some overhead. And most of that overhead lies in the crossing of the kernel-user protection boundaries, and not in the API per-se. See for example the rationale for the 'stdio' library.

But there are a number of aspects of the current Linux design where for what I think are nakedly "commercial" reasons some assumptions about physical device properties have been embedded in the abstraction layer implementation.

Of these the most imbecilic was the plugging/unplugging "idea" which is based on trading latency for throughput INSIDE THE PAGE CACHE which is wholly inappropriate for a device independent layer and for a number of physical devices too, in particular low latency ones (and it has some bizarre side effects too).

It may well be that for some device technologies trading latency for throughput is worthwhile, but this should be done in the device driver, and should be configurable or at least it should be possible to disable it.