I run some of my programs via the parallel computing toolbox using a reasonably powerful machine (20 Cores) to accomplish long running jobs (20 Min - 24 hours). It has recently been brought to my attention that since Matlab doesn't actually make use of the hyper-threaded cores, that the processing may see performance improvement by turning this off in the BIOS. I turned off the hyper-threading and then ran a speed test utilizing all 20 cores on the machine. For some reason, even though I was utilizing a higher percentage of overall processing power available on my machine, the jobs actually ran consistently slower when the hyper-threading was turned off.
Can someone help me to understand the benefits or drawbacks of turning hyper-threading on/off. Should I see performance improvement from turning this functionality off? If so, why do my results differ from my expectation?
Thanks in advance for your help, Brian