Some pages in Magento were giving just a white page, with no indication of errors in Zend Server console or log files. This was apparently a memory issue, so I restarted the web server and all was fine.
One issue I noticed was the server “setroubleshoot” was taking 12% of the systems memory. This program just logs issues with SELinux and it seems SELinux doesn’t like my Magento install. I have SELinux just set to ‘warn’, but I may want to disable it all together. I stopped the ‘setroubleshoot’ program and turned it off with chkconfig.
Did this help you out? It took me a few days to piece together all this information together, I hope this saves you some time (who knows, maybe the future me will be thankful I wrote this down). Let me know your thoughts. firstname.lastname@example.org