CUPS 1.4.4 slow - problem checklist?

[John A. Murdie]

> My department which uses CUPS 1.4.4 is finding it rather slow. Is there a standard list of potential problems I could check for? (I can't find such a list in the documentation.)
>
> I'm seeing a cupsd taking 75-100% of CPU continually ...

The problem seems to have been just two (!) users (in 150 or so) running GNOME's system-config-printer/applet.py. I killed the processes on the desktop PCs in question, and then saw other users print jobs go through with the CPU% at 3%, more quickly than I've seen in the few weeks since we did a new Linux install here (in which, presumably, the current version of the printer applet arrived for the first time). When I start the applet myself, cupsd CPU% rises steeply again.