It's occasionally useful for me to know what the sizes of xdr-encoded nfsv4
ACLs would be likely to be.  So:

length of ACL is 4 + (length of first ACE) + (length of second ACE) ...

length of one ACE, in bytes: type + flags + mask + name length + name
	= 16 + (length of name rounded up to 4)
lengths of common names:
OWNER@: 6 + 2    =  8
GROUP@: 6 + 2    =  8
EVERYONE@: 9 + 3 = 12

So, length of minimal six-element ACL:
	4 + 2 * (16 + 8) + 2 * (16 + 8) + 2 * (16 + 12) = 156

With a mask:
	4 + 152 + (16 + 8) = 180

Length of my own username:
bfields@citi.umich.edu: 22 + 2

ACL with m user entries the length of my name, and n group entries of the
same length:

	180 + 3 * m * (16 + 24) + 3 * n * (16 + 24)
	= 180 + 120(m + n)

So a page, e.g., could hold ACLs with names of length up to 24 and m + n up to
32, which seems pretty reasonable.

Worst-case name lengths can be arbitrarily bad, though.