I know i'm not alone in this problem and there are others out there and I understand this is all related to beta and preview software so I'm not expecting a permanent fix right now.
I have also read several other threads about this issue:
http://community.office365.com/en-us/f/153/t/299887.aspx
http://community.office365.com/en-us/f/153/t/299059.aspx
http://community.office365.com/en-us/f/153/t/298682.aspx
The basic solution proposed in all of these cases is to delete the OfflineFIleCache folder in the user's library. This does temporarily solve the problem for me but it does reoccur consistently for me. Last night I deleted the OfflineFileCache folder and once the issue was corrected I shutdown my macbook pro. Half way through the workday today OneDrive "encountered a problem" (crashed) and now the issue has returned with the same basic symptoms as everyone else.
If there is anyone from Microsoft reading this I'm willing to provide you with logs or any other troubleshooting steps necessary to assist you in resolving this in future releases of the software. Just get in touch and I'll work with you on it.
My System:
Macbook Pro Retina (late-2013) with Yosemite and all available updates.
Office 2011 for mac
Office 2016 for mac preview
OneDrive for Business Mac Beta
My symptoms:
OneDrive for Business Mac encounters a problem accessing the file cache upon launch of the application.
If you choose to repair the problem the upload centre application launches in the background and OneDrive continues to launch.
OneDrive appears to run properly except that the application consumes all available CPU as long as it is running. Quitting the app does return the CPU to normal and oddly enough if you click on the OneDrive cloud icon in the menu bar to display the drop down options, the CPU usage also drops to a normal idle/background state. As soon as you leave the menu the CPU again ramps up to consume as much CPU as is available.
This all began after installing the Office 2016 for mac preview. I was using OneDrive for Business for Mac before installing the preview of 2016 and had no issues like this.
If I quit the app, delete the OfflineFileCache folder from this location: ~/Library/Group Containers/UBF8T346G9.Office/Microsoft/AppData/Microsoft/Office/15.0/ and then reboot the OneDrive for Business App again functions and launches correctly with no high CPU usage. The problem however reoccurs consistently for me within the next day or so of usage.