Is hyperthreading recommended for use with TM1?
TM1 fully supports hyperthreading (HT). However because TM1 is largely a computation engine and is largely compute bound it does not benefit much from HT. HT has the most benefit to applications that are I/O bound. TM1 is multi-threaded in reporting mode (data read mode) and will consume all available processors. NOTE: to actually see this you will need a minimum of 2 active threads (users). Hyperthreading works because it decreases the time and processing required switching between threads. In situations where one execution is stalled for any reason, switching to another thread will utilise the processor much more efficiently. Hyperthreading uses fewer resources doing this switch, it's essentially free, and therefore it's a huge win.
TM1 is different, its 100% memory based. It doesn't do a lot of I/0 therefore its threads are rarely stalled, therefore you don't gain quite so much (if anything) with TM1 if you have HyperThreading enabled.
The recommendation by development is for the customer to run benchmark tests on their system to see whether there is any benefit to having hyperthreading turned on or off.