I am using
ac-c-headers and whenever I type
std:: There is a long (~30 seconds) pause, presumably while the candidates list is populated. This happens every time, which suggests that there is no caching to speed things up for the next time.
Is there a way to avoid the pause after every time I type
Using the emacs profiler, I have now discovered that the pretty much all of the time is being spent in the functions
semantic-analyze-current-context. This suggests that the real problem probably lies with semantic. I have also learned that including anything from the Boost libraries causes a significant increase in the amount of time required for semantic to return possible completions.
(In case it makes a difference, I am using Emacs 24.5 on Linux)
auto-complete-mode, but 30 seconds is really long! If you don't get an answer here, consider contacting the package maintainer -- 30 sec is long enough to suspect a bug. You might also try debugging it, with
M-x debug-on-entryfor the function that performs the completion.