[PATCH] fadvise(2) system call

[perryh at pluto.rain.com]

John Baldwin <jhb at freebsd.org> wrote:

> I have been working for the last week or so on a patch to add an
> fadvise(2) system call.  It is somewhat similar to madvise(2)
> except that it operates on a file descriptor instead of a memory
> region.  It also only really makes sense for regular files and
> does not apply to other file descriptor types.

Seems to me it could also make sense for disks and geoms.  The
access patterns used by dump(8) and fsck(8) are likely different,
from each other and from those typically encountered in the course
of filesystem activity -- and I wouldn't be surprised if mounted
access patterns tended to differ among, say, ufs, zfs, and msdosfs.
Granted the pattern of disk activity created by a filesystem will
vary greatly, depending on the patterns of file access that the
filesystem is servicing.