We have a virtualized environment using VMware vSphere 5.0 U1 which hosts our Microsoft SQL Server and have very poor performance. the host server is a HP DL360 G5 with xeon X5450's, and the disk space comes from a SAN on HP P4300 G2's using SAS2 and Iscsi.
The server itself has 3 cores at 3.00ghz, 12gb memory and 1gbps nic, running Server 2008 R2 Enterprise and SQL Server 2008 R2.
There are three databases, one is 180GB used for Microsoft Dynamics CRM, one is 50gb used as a data warehouse and the other is 500mb used by Document Logistics (a document management system)
There is also an analysis services cube and reporting services running on the same server.
Network and CPU usage are both low, except when the SSIS packages update the data warehouse when CPU sometimes reaches 100%.
Memory is always maxed out and the system reports excessive paging.
I am uncertain if just throwing more memory at the problem will help - and if so how much should I use - or if it's more due to being virtualized and having a separate server with dedicated local disks would be the best option.
UPDATE --- databases are set to limited memory and the total limits are kept withing the 12gb total all of the files are on one disk and the OS/Programs on another Autogrowth is set to 1mb, unrestricted Indexes are left to host program defaults but seem ok server is generally slow, assume due to memory no mantinence plans set up Logs are all aroung 100mb except the one for CRM which is 900mb