Next: Mode Lines, Previous: Faces and Fonts, Up: Various

### 9.7 Compilation

Remember all those line format specification variables? `gnus-summary-line-format`, `gnus-group-line-format`, and so on. Now, Gnus will of course heed whatever these variables are, but, unfortunately, changing them will mean a quite significant slow-down. (The default values of these variables have byte-compiled functions associated with them, while the user-generated versions do not, of course.)

To help with this, you can run `M-x gnus-compile` after you've fiddled around with the variables and feel that you're (kind of) satisfied. This will result in the new specs being byte-compiled, and you'll get top speed again. Gnus will save these compiled specs in the `.newsrc.eld` file. (User-defined functions aren't compiled by this function, though—you should compile them yourself by sticking them into the `~/.gnus.el` file and byte-compiling that file.)