If you have NAT or firewall issues, or problems with large packets
(due to tunneling) or fragments getting dropped, or multiple large
packets in a row, they will show up with larger files but not tiny
ones.
Run tcpdump on the server and client (or whatever machines are
trouble) and try to provoke the bad behavior and see what's happening.

You might also put

validateattrs=20

in venus.conf to avoid causing fragments.

(I run coda over IPsec, and then over wireless, so I like to avoid
fragmentation, and thus keep payload low enough that after IPsec
overhead it still fits.)


-- 
        Greg Troxel <gdt_at_ir.bbn.com>