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Photoshop "only" using 100% of my CPU

I have seen things take up >100% of the CPU in Activity Monitor. I am talking about when you look at the processes in activity monitor, not just theoretically.

And thank you for the feedback on the website. What do you think I should do to make it less offensive?
 
CPU utilization is usually measured per virtual core. Your machine probably only has 2 physical cores, but thanks to Hyperthreading, the OS sees four cores. But since these four virtual cores share the resources of two virtual cores, it is hard to utilize them at 100 % each.

In any case, software needs to be able to parallelize workloads in order to really take advantage of more than 1 core. There are certain workloads which you can parallelize easily (e. g. render images or apply certain types of filters) while for others, you can't (e. g. when you need to wait for the result of a computation to start a new one). Then there are problems which may be parallelizable, but they are not easily parallelizable. Most parts of Photoshop are not programmed to take advantage of several cores, so what happens is that Photoshop will utilize one core to the max (100 %) and the others are twiddling their thumbs.

As you always have background processes running, even normal users benefit from dual core CPUs which are now standard.
 
OreoCookie said:
CPU utilization is usually measured per virtual core. Your machine probably only has 2 physical cores, but thanks to Hyperthreading, the OS sees four cores. But since these four virtual cores share the resources of two virtual cores, it is hard to utilize them at 100 % each.

In any case, software needs to be able to parallelize workloads in order to really take advantage of more than 1 core. There are certain workloads which you can parallelize easily (e. g. render images or apply certain types of filters) while for others, you can't (e. g. when you need to wait for the result of a computation to start a new one). Then there are problems which may be parallelizable, but they are not easily parallelizable. Most parts of Photoshop are not programmed to take advantage of several cores, so what happens is that Photoshop will utilize one core to the max (100 %) and the others are twiddling their thumbs.

As you always have background processes running, even normal users benefit from dual core CPUs which are now standard.
Click to expand...

This.

If you fire up After Effects you'll see it use all cores.
 
OreoCookie said:
CPU utilization is usually measured per virtual core. Your machine probably only has 2 physical cores, but thanks to Hyperthreading, the OS sees four cores. But since these four virtual cores share the resources of two virtual cores, it is hard to utilize them at 100 % each.

In any case, software needs to be able to parallelize workloads in order to really take advantage of more than 1 core. There are certain workloads which you can parallelize easily (e. g. render images or apply certain types of filters) while for others, you can't (e. g. when you need to wait for the result of a computation to start a new one). Then there are problems which may be parallelizable, but they are not easily parallelizable. Most parts of Photoshop are not programmed to take advantage of several cores, so what happens is that Photoshop will utilize one core to the max (100 %) and the others are twiddling their thumbs.

As you always have background processes running, even normal users benefit from dual core CPUs which are now standard.
Click to expand...

This is helpful, thanks!
 
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