I've got the linux-4.17 kernel tree around, 61,322 files.

My desktop is running ubuntu-18.04, is an i5-3570, and has a fairly quick intel SSD.

Running "blush -R -i FunctionName ." takes 15.090 seconds and finds two files.

Running "ag -i FunctionName", finds one file, missing one in .clang-format.

Running "ag -i -u FunctionName", finds two files and makes 0.64 seconds.

So somewhere around 20-25x faster.