I'm wanting to virualize my primary hosting server which is currenty running on a physical box. My concern is that today, it's exreemly responsive. You type in the URL to any well coded, light website on the physical server and the site is loaded virtually as soon as you press the button. I want to make sure that I won't sacrifice that responsivness if I move towards a virtualized setup. I have about 80 active accounts, running on a dual xeon 2.8 with 2GB ram physical server. I want to move to a VMWare ESXi based VM on a 8-core AMD Opteron 6128 2.0 with 16GB of Ram, and I would dedicate 2 cores and 4GB to the Cpanel CentOS 5 VM. Does anyone have a VPS Cpanel installation running on VMWare? Does it take a performance hit or responsiveness hit because of it?
I have a couple of very busy cPanel servers (over 1000 sites each) running virtualized. I give them 4 cores and 4GB RAM each. I haven't tried 2 cores so I don't know if they really need all 4 but that's the way I have them configured. Update: I should say, they are virtualized on VMWare ESXi 4.1 servers.
I suggest performing some tests by moving accounts to the virtualized server, then running tests with Apache's ab tool and mysql's mysqlslap tool. Here are discussions on using Apache's ab tool and the mysqlslap tool: Howto: Performance Benchmarks a Webserver MySQL :: MySQL 5.1 Reference Manual :: 4.5.7 mysqlslap Of note, you'd need to have MySQL 5.1 to use mysqlslap as it isn't available by default for MySQL 5.0