Using Single Apache SSL/Non-SSL in Production?

tck1000 asks: "I currently maintain some legacy webservers, running Apache 1.3.x on Linux, on x86 hardware. Two separate daemons are used. One to serve SSL vhosts, and one to server non-SSL vhosts. Each of these servers also is compiled with PHP, mod_perl, and JServe, and also works with a Tomcat servlet engines. In the process of planning an upgrade path, I've thought about using a single daemon to serve both the SSL and Non-SSL vhosts. Is this a good idea?"

"These webservers serve about 4 million hits a day across all the vhosts. I'm worried about memory usage if every httpd process has to load mod_ssl, as well as everything else they load.

I've been searching for comparisons between running 2 daemons (and the associated effort in maintaining/upgrading/patching), vs. running a single daemon (with any added overhead it entails).

I've found a lot of examples of how to do it, but not much on the why's.

Comments, Opinions, Ideas, Links?"