add CcdCallBacksReset() to header file (or improve callback frequency)
Trying to poll the GPU every 0.1ms I get much lower frequency when the PE is busy. The expedient solution is to add a call to CcdCallBacksReset() immediately before every call to CcdCallFnAfter(). This resets the message skip count, which CcdCallBacks() tunes to 5ms, and instead typically checks the callback after every entry point.
I currently provide a CcdCallBacksReset() prototype in the NAMD source code, but it would be better to expose this function in a Charm++ header file, or call it automatically inside CcdCallFnAfter(). It would also help if CcdCallBacks() tuned nSkip to the shortest registered callback interval rather than a fixed 5ms.