IMAGEN laser printer slowness

[Robert Walton]

I am interested if anyone knows anything about the speed, or lack thereof,
of the IMAGEN laser printer.

For example, we have a iroff (ditroff) job of 47 pages that

(1) when printed with pagereversal on seems to take 25 minutes
    for the imagen printer to process and 5 minutes to print

(2) when printed with pagereversal off (run dimp -t first and edit output
    to change `pagereversal on' to `pagereversal off' before using
    lpr -v) the first 10 pages take 2 minutes to print (measured from
    job header page of previous job) whereas each succeeding 10 pages
    takes 8 minutes to print

This is with a new imagen processor with 1.25 Megabytes of memory.
With the same processor and 0.75 megabytes we also noticed the same
slowdown problem as in (2) with imprint -2 -O -F, but the extra memory
cures that.

We are using Ethernet communications, but do not believe the problem
lies in slow communications.  The 47 page iroff document above requires
that 179 Kbytes be sent to the IMAGEN processor, about 5 Kbytes per page,
which should be easily doable in 6 seconds per page.

10 pages per 8 minutes is not very good speed, especially since the printer
is bottlenecked during the processing (you cannot precompute everything
overnight as you could with a versatek).  Does anyone have any
contrary experience (for large documents) or cure?

We do not claim to have fully and carefully investigated this problem yet,
and are hoping someone out there might know something that would
save us some effort.

Please include `walton at ll-xn' directly in any responses as I am
not on the wizards mailing list.