SQL memory management in active/active configuration
Hi, I will have 4 nodes in an active/active/active/active configuration. Each node will have 3 SQL instances installed on it. Each node has 256GB RAM. I know I can set the limit each instance can use, but the more memory SQL gets, the better it runs. Ideally, I would set each instance to use 80GB or so. Roughly 1/3 of the node's memory, leaving some for the OS and Veritas. What happens if one of the nodes goes down? Where would the newly failed over instance get it's memory from? Is there a way to manage this? Should I let SQL manage it? I don't want a run-away query on one instance to hog all the node's memory though and affect the other instances on that node. What are my options?