Re: Multiple DBs vs Multiple instances

----- Original Message ----- From: Terrence Mu.... <terrence@wagerworks.com> At: 3/13 14:23 > What are the pros/cons of have multiple databases in one instance > as opposed to having multiple instances with just one database. For multiple databases: Makes better use of system resources by sharing cache, memory, and system disk overhead. Fewer processes on the system. If different databases have different load peek times the only need to configure for one peek level not both. Simpler maintenance, one engine to tune, no problems with overtuning one instance grabbing system resources from other instances. If databases in the instance have very different types of queries one from the other then they tend not to interfere for resources (OLTP needs many locks but not much cache, DW & DSS do not need locks at all but need lots of cache) For multiple instances: Less interdatabase contention for server resources like cache and locks. Can tune each instance differently for different types of queries. Maximize shared memory in one, cache in the other. Short queries do not have to wait while PDQ queries complete using large portions of available memory and CPU resources. Art S. Kagel