- What's the difference between the previous version?
4 threads.
Old versions allowed up to 8 threads and 2020.110 allows up to 12.
- Is it useful to use more threads than there are physical core's? for example with a 8core/16 thread CPU?
The number of physical cores doesn't matter as much as supported threads. QU shows on the splash screen how many cores and threads are supported on your system. If it says 6 cores, 12 threads then you should run 12 threads if you want the fastest performance. If it says 4 cores, 8 threads then you should run 8 threads for fastest performance. If it just reports "4 cores", then your system doesn't use thread optimization and it supports 4 threads (same as the number of cores). Leaving QU's Multi-threading settings on the default "Auto" setting takes care of all that.
Many of the latest high end consumer CPU's are 6/12, 8/16, or 12/24 cores/threads so 2020.110 will process prints, thumbs, and raws significantly faster on those systems. Using more threads than you have physical cores makes sense if your system supports more threads than physical cores. But using more threads than your system's
thread count will have limited (if any) benefit and will render your system unusable for any task other than the one using those threads, meaning you won't be able to perform other tasks while waiting for the high thread-count task to finish because your high-intensity task is using all that the CPU supports.
Mike