I'm searching for a string among 2500 files spreading over a directory tree. The performance number:

Another program: 2 seconds
EmEditor: 9 minutes

This translates to 4.6 files per second for EmEditor v.s. 1250 files per second for the other program.

Another interesting observation. There are two types of files, one with .rst extension and one with .html extension. The search seems to go much faster with .html files. It takes 65 second to search through 1000 .html files. This translates to 15 files per second. Not great, but much better than average. The total files size of the .html files actually make up 75% of the original search.