I'm managing a site that gets about 2 million page views a month and the log file does fill up really quickly! We're still running 4.5 (actually it was the 4.x beta release). Anyway, as a temporary fix, we let newsyslog roll the -error.log files every hour. This has kept the log file manageable. Here's the syntax (FreeBSD box):
/usr/local/aolserver/log/openacs-4-error.log nsadmin:nsadmin 600 2 10000 * Z
