what exactly is "wasted swap space"

[Brian V. Smith]

I have several Vaxstations, some II's and some 2000's.  For some reason
on one (only one) of the 2000's, we are seeing a LOT of "wasted" swap space.
Each time I start an xterm (X11R4, MIT) approximately 500k more is put in
the "wasted" category by pstat -s.  
On all 6 of our other machines, only 128k is "wasted" for each xterm started.
Moreover, the amount "used" according to pstat, is about 1000k for each xterm
vs 700k on our other machines.
All are running Ultrix 3.0.
Why is there "wasted" swap space?

Can anyone shed any light on what is happening?  I will be glad to provide
more details if necessary.   Here is the output from pstat -s:

22864k swap configured
        21894k used (2457k text, 0k smem)
        968k free, 9004k wasted, 2k missing
avail: 2*256k 1*128k 1*64k 3*32k 2*16k 136*1k

-- 
Brian V. Smith    (bvsmith at lbl.gov)
Lawrence Berkeley Laboratory
I don't speak for LBL; they don't pay me enough for that.