Re: Reserving blocks without actually creating files

Is it possible to mark blocks on a filesystem as used without actually
putting anything into those blocks? It is like creating a sparse file
but actually putting all the blocks aside.
[snip]
So is there an easy way to "fake" that the filesystem is already
pretty full without actually copying 10TB of data?

If the operating system and file system are new enough to support
fallocate(), then: create a file for writing (thus empty), fallocate(),
sleep() without close()ing the file descriptor. There may be limits,
so you might have to use many files. Actual space exhaustion might
revoke previous unused reservations, but it's worth a try.

--
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