my Mac is running OSX Yosemite 10.10.2.

I recently found out that in my console such messages:

> [A process name and its pid]: The function ‘CGContextErase’ is obsolete and will be removed in an upcoming update. Unfortunately, this application, or a library it uses, is using this obsolete function, and is thereby contributing to an overall degradation of system performance.

would occur for *every* window I opened.

I tried `$ sample -e -wait [Application Name]` then launch the application, but in the report I can't find any call to `CGContextErase`.

Is there anyway to reveal what is behind all this?

Following is a screenshot of Console messages filtered with word `CGContextErase`:
![a screenshot of console](http://d.pr/i/1kJHo+)