The dataspace usage is certainly a good thing to check, but there are at least a couple of other possibilities:
The paging rate numbers are across time, whereas the Q ALLOC PAGE output is instantaneous. It could be that there's a low volume of paging to/from p aging DASD going on, but the pages that are read in are immediately changed, wh ich would cause CP to discard the copy out on paging DASD when CP notices the page change. So it needn't be the same page read 13 times a second, it could be a bunch of different pages which are then immediately changed, for which CP then discards the paging DASD copy. I'd have to check, but it seems possible that demand paging of spool page s from (and even possibly to) spool volumes could account for this, I'd hav e to check how those get counted. In particular, if you have a very lightly u sed NSS or DCSS, that only tends to be loaded by one user at a time, and it i s frequently purged and then reloaded, the initial page fault block reads f rom spool might show up like this. - Bill Holder z/VM development, IBM
