It's possible a bug crept in somewhere between Apache releases
But I'm not ruling anything out just yet. Still, changing from nph-zms to zms seems to have fixed my problem.
I fixed my problem as I mentioned above, but looking closer, I see that firefox (and I think all gecko browsers) have the same problem. The monitor window I had open shows two cameras and the firefox (and other gecko-based browsers) started eating up about 1/10 MB per second. That memory was only ...
Often, when I opened the monitor window, there would just be a little picture-placeholder-icon that Firefox shows before it's loaded an image. To see the picture, I would have to refresh the window once or twice. Every time I refreshed the monitor window, a new nph-zms process would start, but the ...