> > Yes, I made note of that in my OP on this thread.  But is it enough to
> > end up with 8gb of non-compressed files measuring 8gb on
> > reiserfs(linux) and the same data showing nearly 9gb when copied to a
> > zfs filesystem with compression on.  
> 
> whoops.. a hefty exaggeration it only shows about 16mb difference.
> But still since zfs side is compressed, that seems like quite a lot..

That's because ZFS reports *all* space consumed by a file, including
all metadata (dnodes, indirect blocks, etc).  For an 8G file stored
in 128K blocks, there are 8G / 128K = 64K block pointers, each of
which is 128 bytes, and is two-way replicated (via ditto blocks),
for a total of 64K * 128 * 2 = 16M.  So this is exactly as expected.

Jeff
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