All CPU cores running 75 to 95% and fans always running
I am using a MacBook Pro 2.8GHz running El Capitan 10.11.5. On my PC I have been using Acronis True Image for years as my backup software. It has only gotten better over the years. That is why I jumped at the opportunity to run the Mac version. That was a huge error on my part.
I just returned from an Apple Genius Bar appointment not being able to use my Mac for almost a week. All 4 cores were running between 85 to 95% all the time the minute I started my Mac. I made the appointment thinking my CPU was faulty but after Apple analyzed the trouble they said it was Acronis that was causing my trouble. Returning home I started my computer and the cores all started as if they were under a high load and the fans started running even though my computer was cold. As fast as I could I deleted Acronis all cores and fans dropped immediately dropped to normal.
I’m pretty mad that Acronis would release a program so flawed and not ready for prime time. I have contacted Acronis about my problem but so far have not received a reply.
I haven't heard anyone else report this so far. With Acronis installed, run system monitor and verify yourself what is using the resources.
What year is your macbook pro? Is it officially supported for El Capitan? I have 2006 macbook pro's that seem to run it fine, but of course, Apple doesn't officially support it so could be issues on unsupported hardware
I have upgraded a 2013 macbook air to El Cap and battery life cut in half and fan runs much more now - have reinstalled OS X from scratch with no change. There are many others complaining about similar issues with their Macs as well even with Finder maxing out CPU. These posts have more info about this type of behavior with El Cap and may offer a solution for high CPU usage in general
10.11.6 is out now, maybe try upgrading as it may fix a possible issue with 10.11.5 on your system.
Just curious, but did you upgrade the hard drive at any point. When i upgrded the HD in my iMAC using a non-apple HD, it did not include a heat sensor. As a result, the system fans would run at 100% all the time because it couldn't tell how hot the drive was getting. I ended up installing a free fan control software so that I could manually set the fan speed. Not ideal as sometimes the fans do need to be able to kick up automatically, but this was all due to not having a properly connected heatsensor on the new hard drive.