I see what you mean, well for the caching options you have selected APC is well liked, however I would check on development to see if it is still active. EAccelerator is what I use and like it quite a bit. If you go with FastCGI your memory requirements will significantly increase. If it is your first time using it, you will need to watch it quite often at the beginning to set the appropriate number of php processes to spawn per user, time to allow processes to run etc.
FastCGI + Varnish + eAccelerator + CloudLinux is my current thought.
suPHP + Varnish + CloudLinux is if I leave it unchanged.
Right now, mostly seeking opinions. Asking here, asking some hosts I use/respect. I'm mostly interested in performance, but without sacrificing ease. I want to have a server that works, not something I have to baby along all the time.
The server has 32gb of RAM, so not really concerned there. I'm thinking I/O would give out before anything else (RAID-10 SAS). Honestly, CPU isn't much concern either, as RAM and I/O is always the main issue.
I have another server with 8gb, so RAM use is a bit more of a concern. Doing the 32gb first.
These obviously are not VPS. I'm pretty set with all my Linux VPS using things like nginx. I'm not at all a cPanel-only newbie.
MariaDB is also too hackish with cPanel. Can't use it. (In use on my panel-less VPS, however. Very nice.) Someday cPanel needs to include php-fpm, nginx, MariaDB, etc ... or prepare themselves for the day a competing panel comes out. They're far away now, but ISPConfig and Virtualmin especially have potential.
I think I've eliminated mod_ruid2 as an option. From what I read earlier, even cPanel has backed off suggesting that after 2 years of pushing it. Hence a reason I've asking here, reading current docs, etc. Want to make sure I'm with the times!
The setup you plan to have is great but there are a couple of things to note. The key here is your statement about "not sacrificing ease"
While I don't consider FastCGI difficult to setup, it will need constant attention, until your server no longer adds any new sites. The reason being is that FastCGI will launch processes and keep them available in memory even if no script is using them. 10 Sites, Low traffic - not a big deal. 200 Wordpress sites, Some with heavy traffic- could be a bid deal depending on what plugins they are using, traffic peaks vs other sites etc. Without knowing exact details about what you will host when you start and the final number of sites you will host on the server, you will need to regularly adjust the factors I mentioned like maximum number of php processes, how long they stay in memory, etc. Then add to it 3 to 4 separate caching mechanisms that might be in use - Caches like varnish will be one type. Then you have Eaccelerator which will be for you PHP. Then, back to Wordpress, you have any caching plugins your hosted sites might use. In addition, if the sites that are hosted are poorly coded, they could consume more ram than necessary without a performance increase. I have seen a Wordpress site require close to 500 mb in ram for just one site. Not saying the same will happen to you. But if enough sites were demanding resources, and you have not been regularly updating FastCGI config to keep up, people will start getting timeout errors. Thats probably why cpanel says go with SuPHP - you wont get performance, but you will get ease (although I believe you still have to tweak beyond stock for security). Now I think your planned setup is perfect for your hardware and I definitely recommend a FastCGI implementation of some sort for you.
Cpanel knows that any implementation other than SuPHP or DSO is considered advanced and requires work. Cpanel for all intents and purposes is designed to be as user friendly as possible to keep support costs in check.
Which brings me back to PHP-FPM - You get the security, you get a stable and fast php handler that wont need much tweaking, and you get to use PHP's built in cache which is a significant improvement over the currently available ones (Xcache, Eaccelerator),etc... But the trade off is you will have to build this utopian handler yourself. The instructions are on Cpanels forum so you wont be flying blind so to speak.
As for MariaDB, the replacement was like 4-5 steps total. Does not really qualify as a "hack". Upgrades and updates will perform perfectly for Cpanel as long as you follow the instructions on Cpanels site. MariaDB can be updated from the command line with a single command if necessary. But it's definitely good to consider for multi site environments as every paper I have seen says it kicks MySQL's butt. If your concerned about stability or viability, tons of big names are using it production now. Heck this forum might even be using it.