I am running Mathematica 220.127.116.11 on a MacBook with OS X El Capitan, version 10.11.6.
I used to have no problems using Mathematica. Then recently, it started to be extremely slow. Even for the simplest calculations (I mean trivial stuff, like 8 times 9). If the calculation is trivial I eventually get the answer but after more than a minute of work, even to find 8x9.
I checked the CPU usage and I see that even when I ask trivial calculations, the MathKernel process shoots up above 99% of CPU usage. I also noticed that if I abort the calculation, MathKernel sometimes remains there, still taking above 99% of the CPU. If I abort a second time (even though as far as I can tell from the Mathematica window no calculation is running), then the MathKernel process will disappear.
The most puzzling think is that Mathematica used to run fine, even with complex calculations. I have not made any changes or updates lately and it started acting this way. Now it is useless since it cannot do even simple calculations in a reasonable amount of time.
Can anyone help?
Thank you in advance!