On Tue, Mar 06, 2007 at 06:36:09AM -0800, Ulrich Drepper wrote:

Christoph Hellwig wrote:

quoted

fallocate with the whence argument and flags is already quite complicated,
I'd rather have another call for placement decisions, that would
be called on an fd to do placement decissions for any further allocations
(prealloc, write, etc)

Yes, posix_fallocate shouldn't be made more complicated.  But I don't
understand why requesting linear layout of the blocks should be an
option.  It's always an advantage if the blocks requested this way are
linear on disk.  So, the kernel should always do its best to make this
happen, without needing an additional option.

There are HPC workloads where you have multi writers on multiple machines
that write to different parts of a file.  You preferably want each
of those regions in separate allocation groups.  (Or tell the customers
to use separate files for the regions..)