Hi all, I'm currently running a monte carlo simulation on my laptop, which has an i7-3630. I've set it up to use 4 cores (the CPU, as you may know, is quad core with HT, making a total of 8 logical cores). The strangeness comes when I look at the CPU load, and the total load on the CPU is 74%. Task manager is showing 8 core load graphs and tells me that the CPU has 4 cores and 8 logical processors, but, to my simple mind, 4 cores is only 50% of 8. Any idea why the system has decided to only be a 6 core machine? I did run the code with 6 threads, and that loaded up the CPU to 100%. I also ran a case with 8 threads and that was slower than the 6 thread case. This indicates, to me, that something is wrong with my CPU. Thanks, Andy Full spec: Scan 3XS system (bought in Jan 2013), i7-3630QM, 16GB RAM, 120GB SSD, 500GB HDD and an AMD Radeon (can't remember the GPU )
I think where yoou have gone slightly wrong, is that the CPU is a 4 core with the ability to run 8 threads with hyper threading. It's not a true octocore in the same as a dedicated server chip would be. It's the the abilty to run 2 threads per core as opposed to a straight forward quad core with out hyper threading. What I would do is let the program make its mind up how it wants to run rather than allocating it cores. Basically if it needs 8 threads it will use them. but if not the CPU will only use what it needs and may even sit idle on one core until a background process needs to do some thing. In the past I have seen 1 or 2 cores idle and asked why and the simple answer is they're not needed.
Sorry for taking so long to get back on here. Thanks for your reply. The code is not that intelligent. I have to tell it how many cores to run on. Previously, if I told it to run on 4 cores, it would use 50% of the cpu, but now, that has changed. And I'm not sure why. Strange, unless the logic on the CPU has died...
Is it possible that something else running in the background is causing the additional CPU usage (e.g. maxing out two more threads)?
