After years of Plone/Zope running on a 10.5 web server, this last weekend I started seeing the zope logs filling with errors saying “[420] Too many open files”. One, I hadn’t seen this before, and two, I couldn’t figure out why it was happening after years of solid use.
So, looking around online, it appeared that 10.5 just set the max files open per user to an awfully small limit (especially in the server version)… 256 files per user! Since I use a zeo/client setup, and use FileSystemStorage for storing files outside the zodb, I easily had this many files open. Again, why is this just happening after years?