Performance with windows emacs 25.1 (original) (raw)

Using irony as the primary completion enigne in company with the latest emacs has a visible delay until showing candidates for a 210 kb .c source file.

After aelp-instrument-package I have this (for emacs 25.1):

• irony-completion--send-request: 0.5411360333 (time per call)

And for emacs 24.5:

• irony-completion--send-request: 0.0746239 (time per call)

This is for the same .c file at the same position. If I do a elp-instrument-function for process-send-string, 99% of that time is spend there.

I first thought that this is an issue with process-send-string but I did a small test with emacs:
I created a small program that read from stdin and wrote "SUCCESS" each time it read something and I sent it the same file from emacs with process-send-string, and the results were very different:

For emacs 24.5:

• process-send-string: 1.0931796 (time per call)

And for emacs 25.1:

• process-send-string: 0.6128976 (time per call)

I repeated the tests several times, and the results were the same, with small variations (2-5%).

So the issue isn't with process-send-string, but maybe it's something internal to irony-server.

Note: I used emacs 24.5 from msys64 (mingw64 version) and an emacs 25.1 compiled by me with the same flags as emacs 24.5 with mingw64.