Check #1: Are you using the latest version of the Lima app?
We are always working on performance improvements on the Lima software. Make sure you are running the latest version of Lima to benefit from all the advantages we've built into the application. Check your Settings (Lima Preferences / Settings) to see if there's a new update available.
Check #2: Are you running the latest Mac OS X?
There is a known issue under Mac OS X Mavericks (10.9) that can cause Lima, or ecore, to use 100% of your CPU. This is because of limitations in the technology we use to display Finder overlays. We recommend upgrading your OS to the latest version, or at least to Yosemite (10.10).
Check #3: Are you running any anti-virus or security software?
Managing your files, ecore will frequently receive requests from file-level security and antivirus software which need to access your files. That is why ecore consumes a lot of CPU.
We recommend avoiding using these security tools on Lima, by setting up your security app or anti-virus to bypass the Lima drive, Lima app, ecore app, etc. (e.g. by adding it to an exception list or removing it from the scan path).