speed enhancements for dbm(1)?

[G A Moffett]

I am running the pathalias(1) program using the dbm(3) routines,
and I am finding most of the time spent by the program is in
the dbm routines, particularly delitem()!

Does anyone have some speed enhancements for dbm(3) that would
help?  (No assembler unless it's S/370!).

PS -- it's not that UTS is slow (we generate the full pathalias(1)
database -- 3775 lines + *.pag + *.dir -- in ~20 CPU seconds[1]), but
I'm unaccustomed to not having a command finished before I am ready to
type the next one.
--
[1] An Amdahl 470/V8 running UTS 1.0; this time is unofficial
-- 
Gordon A. Moffett               ...!{ihnp4,cbosgd,sun}!amdahl!gam