On Friday 08 September 2006 07:08, Ronan KERYELL wrote:
> First I would say it is possible to mkfs the disk before each new usage to
> have clean data structures with less overhead (no fragmentation...).

Not really necessary; on any modern filesystem (and a few very old ones), 
emptying the filesystem will clear any fragmentation that might have 
appeared.

> Secondly you could choose a file system optimized for big files and
> write-ahead only. It s possible to change the parameters of the FS to push
> even more this behaviour (how many cylinders? block size? no logging on
> the data, no block reserve for fast allocation...).

Well, there's no such thing as write-ahead (the kernel will guess the data you 
will write? :o) but as for big files, the best thing you can do at the FS 
layer is to use a large block size and no data journaling. Setting reserved 
blocks to zero is a good idea, as is using O_DIRECT (as discussed elsewhere).

> Third, what about bad blocks on disk? How to skip them in a raw partition
> if you do not have state-of-the-art disks that do block remapping for you
> in your back-yard (such as SCSI)? Often FS do these tricks for you on
> IDE disks for example.

Irrelevant. All modern drives (IDE included) since MFM have done automatic 
internal remapping.

> Well, IMHO, I would vote for a FS solution except if I have a real
> gain... :-)

As would I.
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