DF-3030 rename M_TEMP leak — before/after vmstat -m (temp rows)
cmd: su -m maxx -c /tmp/rename_leak /mnt/fuse 50000   (100000 renames of ~264-char names)
               temp   98.1K   19.4M       0    390M     141K
=== after 100000 renames ===
DONE iters=20000 (each iteration = 2 renames = 2 leaked M_TEMP allocs of ~264 bytes)
               temp    137K   27.0M       0    390M     180K