Messages in this thread | | | Subject | Re: lack of raw disk devices | Date | Tue, 6 Jan 1998 19:00:04 +0200 (EET) | From | Matti Aarnio <> |
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The direct device access (buffered or not) applications have one benefit which allows them to beat filesystem based file access in speed. Namely the usual indirected-blockpointer scheme at EXT2 becomes more and more slow when the file grows.
Therefore we can't seriously suggest obsoleting raw-device access as long as we can't provide efficient means for continguous file allocation and access with minimum meta-data slowdown. Hmm.. I will think about this...
/Matti Aarnio <matti.aarnio@tele.fi>
From: linux kernel account <linker@nightshade.z.ml.org> > On Tue, 6 Jan 1998, Petrucci, Joseph wrote: > > Wouldn't this solution be just as difficult to implement as Raw > > devices??? > [snip poorly quoted stuff about letting the FS determin read buffering on > a file by file basis] > > No, it would be more difficult.. But it would be 'neat' and have very > good benifits.. A extra flag on the open call to set caching behavior > would be great. > > Raw devices would have comparitivly few benifits. Furthermore, this > feature would make raw devices absolutly unnessassary (just open the /dev/ > file with the approiate open flags).. > > This feature would have great uses for MM apps and such.. >
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