as you probably know, when creating a new service package using the Reseller Manager you can specify a priority (from very low to very high) for SMTP, POP and FTP services (SMTP, POP, FTP).
I have resold a VPS to a client who runs large (4000+) mailing lists and I wonder if increasing SMTP priority would help. I'm already satisfied of the server performance, it's just a matter of optimizing resource usage. Has anyone tried that before? Did you notice any difference?