When you say "block device based", does this exclude network filesystems? It would seem cleancache, like fscache, is actually best suited to high-latency network filesystems.
Does it need to be restricted to inode numbers at all (i.e. can it use an opaque internal identifier like the NFS file handle)? Disallowing cleancache on a filesystem that uses 64-bit (or larger) inodes on a 32-bit system reduces its usefulness.
Cheers, Andreas
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Andreas Dilger
Lustre Technical Lead
Oracle Corporation Canada Inc.
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