I updated recently and now performing simple tasks causes my iMac to bog down and become basically unusable. I can't even drag a small file to the trash without this happening. I have a late 2013 iMac i7, 24gb ram and 512 SSD. SSD is maybe half way full. I've tried resetting PRAM, and Disk Utility First Aide, but nothing works. Some apps open fine, but others take a very long time to open (if they do at all on the first try). Is there something else I can try?