I have a late 2013 Mac Pro (running Yosemite) and have had some problems with a frozen finder recently. When I select a tif/pdf/jpg file it freezes up on me and I have to force quit it. It freezes before it is able to splay the thumbnail of the file I have selected. It sometimes also freezes safari when I click on links or download something, although its a much more frequent problem for my finder.
Any help to get around this is appreciated, its a really annoying problem!!
Edit: spotlight also now freezes but my activity monitor is suggesting all is well
diskutil info disk0 | grep SMART
Let me know what the output is. I am assuming you have only one HDD – Allan Feb 18 '16 at 22:22~/Library/QuickLook
/Library/QuickLook
or/System/Library/QuickLook
– Tetsujin Feb 19 '16 at 08:02