Gutentags regenerating entire tags file every time project is opened

[bernastoc]

Issue and steps
Upon loading a file from my project's root directory, where a 'tags' exists and is current, gutentags will immediately call ctags i.e. "ctags -f tags.temp --options=/home/username/.config/nvim/vim-plug/vim-gutentags/res/ctags_recursive.options ..."

By running htop in another window I can tell when gutentags has finished running. If I close neovim at this point and re-open the same code file, gutentags runs again. Checking the timestamp of the 'tags' file, I can see it's modified each time I open my project file (despite making no changes to the code). I have a rather large codebase so it's impossible to miss when ctags is running since it pegs my CPU for a while.

My Setup
CentOS Linux release 7.8.2003 (Core)
Neovim NVIM v0.5.0-654-g3acfefb63
ctags --version:
Universal Ctags 0.0.0(3f0ea94c), Copyright (C) 2015 Universal Ctags Team
Universal Ctags is derived from Exuberant Ctags.
Exuberant Ctags 5.8, Copyright (C) 1996-2009 Darren Hiebert
Compiled: Aug 5 2020, 15:39:19
URL: https://ctags.io/
Optional compiled features: +wildcards, +regex, +iconv, +option-directory, +packcc

I'm not using g:gutentags_cache_dir nor have I set any gutentags flags other than gutentags_ctags_extra_args.

Logs
gutentags: [job stdout]: ['Locking tags file...', 'Running ctags on whole project', 'ctags -f "tags.temp" "--options=/home/username/.config/nvim/vim-plug/vim-gutentags/res/ctags_recursive.options" --kinds-C=+pxL --kinds-C++=+pxL --fields-C=+{macrodef}{properties} --fields=+{signature}{access} --exclude="one" --exclude="two" --exclude="three" --exclude="etc" "."', '']
gutentags: [job stdout]: ['Replacing tags file', 'mv -f "tags.temp" "tags"', '']
gutentags: [job stdout]: ['Unlocking tags file...', '']
gutentags: [job stdout]: ['Done.', '']
gutentags: [job stdout]: ['']
gutentags: [job stderr]: ['']
gutentags: Finished ctags job.

I couldn't find a tags.log file anywhere, sorry.

Extra Context
Here are the ctags arguments I use:

Manual run at bash prompt:
ctags --recurse
--kinds-C=+pxL
--kinds-C++=+pxL
--fields-C=+{macrodef}{properties}
--fields=+{signature}{access}
--exclude="one"
--exclude="two"
--exclude="three"
--exclude="etc"

And in my init.vim:
let g:gutentags_ctags_extra_args=
[ '--kinds-C=+pxL',
\ '--kinds-C++=+pxL',
\ '--fields-C=+{macrodef}{properties}',
\ '--fields=+{signature}{access}',
\ '--exclude="agent/ti-mibs*"',
\ '--exclude="one"',
\ '--exclude="two"',
\ '--exclude="three"',
\ '--exclude="etc"' ]

Somehow the gutentags generated tags file is 2x the size of the one I generate at the command prompt, but I guess that's a separate issue.

[ludovicchabant]

Hi,

Yes, gutentags, by default, runs on the entire project on the first opened file. The reasoning is that anything could have happened since the last time you closed Vim (pulled/updated the repository is a common one), so gutentags gets ahead of things.

You can set g:gutentags_generate_on_new to 0 to disable this.

Ideally we would just update the tags file by reparsing the source files that are newer (as opposed to the whole project), but I don't know if that's easily possible.

[bernastoc]

Thanks. I let g:gutentags_generate_on_new=0 and I'm seeing the behavior I expected.

[milanglacier]

Hi,

Yes, gutentags, by default, runs on the entire project on the first opened file. The reasoning is that anything could have happened since the last time you closed Vim (pulled/updated the repository is a common one), so gutentags gets ahead of things.

You can set g:gutentags_generate_on_new to 0 to disable this.

Ideally we would just update the tags file by reparsing the source files that are newer (as opposed to the whole project), but I don't know if that's easily possible.

If we restricted scenario on git, maybe we can only update the entire tag file when the HEAD is moved?