Fri Mar 13, 2015 9:29 pm by bob
Yes, you can use the CPU Strategy Wizard so assign cores, or you can do it manually in your character set slots under the performance tab.
Having more cores means that multiple threads in the game (pretty much 0 applications have only 1 thread these day) can execute at once or be scheduled on any core that happens to be available, rather than waiting for a specific core to be available. If you specific allocated core is busy (like responding to an interrupt, like your network card) then your game instance will freeze (or stutter) while it waits for that core to become available.
The natural state of Windows is that processes can have threads run on any core, which is effectively the same as All Instances use All Cores (the last selection in the drop down of the wizard), but sometimes you get the odd game that doesn't like playing nice on multiple cores and starves the other instances, or it just doesn't like multiple cores (not many of those these days).
I'm not sure there is much of an advantage to having 4 cores assigned to 1 instance and 1 core allocated to other instances, unless you have 1 instance to have "priority" over the other instances. i.e. 1 instance that should not lag/freeze and the others you don't care about.
With Hyper threaded CPU's you want to be careful about the allocation of the hyper threaded cores. There are really only 4 physical cores, but each physical core has 2 virtual or logical cores. When using the logical cores, you need to ensure that the appropriate logical cores are paired with each other when setting affinity in ISBoxer. On an i7, this would be cores 1 and 2 are paired, 3 and 4, 5 and 6, 7 and 8. If you pair to logical cores that aren't on the same physical core, you will get poor performance.
My recommendation is always to initially select "All instances use all cores", which is the default Windows position if you didn't use ISBoxer (and Windows is also hyperthreading aware so it can make the better performing choices). If you then find you then have issues caused by CPU starvation due to 1 or more instances hogging cores, then you might want to look into specific core affinity.
