Too high startuptime

[brianhuster]

Today CopilotChat.nvim has too hight startuptime (80ms).

I think I will send a pull request that refactor it a bit to lower startuptime. In the main file (init.lua), I will make it not require any other module at script level (but only in function level). This is to avoid unnecessarily loading all modules at startuptime. What do you think?

[jellydn]

Actually, you could use lazy.nvim to load the plugin on command so the start-up won't be an big issue.

What do you think? @deathbeam

[brianhuster]

I know that, but I just don't like the way Lua plugins often have much higher startuptime than legacy Vimscript plugins just because they often try to load the whole plugin on startup, which is just unnecessary. Also among many active plugin managers for Neovim, lazy.nvim is the only one that supports such lazy-loading. Even if I lazy-load the plugin with the command CopilotChat, then a chat buffer will take a long time to open

For the PR, I will need to make some refactoring. But I would like to ask some questions first.

1. Currently it seems like the table to save config is in the main module. I would like to move it to require('CopilotChat.config').config, is that ok? The table for default config could be in require('CopilotChat.config').default, I think
2. Initializing code should live in runtimepath/plugin/CopilotChat.lua, because that is what it is made for. See Neovim document :h load-plugins

 	The result is that all directories in 'runtimepath' will be searched
	for the "plugin" sub-directory and all files ending in ".vim" or
	".lua" will be sourced (in alphabetical order per directory),
	also in subdirectories. First "*.vim" are sourced, then "*.lua" files,
	per directory.

That would also save users from having to run the function require('CopilotChat').setup() just to use plugin with default config.

[deathbeam]

Im not sure from where is the 80ms coming from, looking at log if I include the plenary loading there as well its like 5ms:

044.613  000.040  000.040: require('plenary.tbl')
044.616  000.102  000.063: require('plenary.vararg.rotate')
044.617  000.130  000.028: require('plenary.vararg')
044.650  000.033  000.033: require('plenary.errors')
044.704  000.053  000.053: require('plenary.functional')
044.707  000.287  000.070: require('plenary.async.async')
044.962  000.053  000.053: require('plenary.async.structs')
044.976  000.157  000.104: require('plenary.async.control')
044.979  000.235  000.078: require('plenary.async.util')
044.980  000.272  000.037: require('plenary.async.tests')
044.981  000.608  000.049: require('plenary.async')
045.572  000.122  000.122: require('plenary.bit')
045.590  000.011  000.011: require('ffi')
045.607  000.506  000.373: require('plenary.path')
045.637  000.655  000.150: require('plenary.log')
045.791  000.027  000.027: require('CopilotChat.prompts')
046.026  000.017  000.017: require('CopilotChat.notify')
046.568  000.034  000.034: require('plenary.compat')
046.574  000.266  000.232: require('plenary.job')
046.579  000.417  000.151: require('plenary.curl')
047.497  000.917  000.917: require('plenary.scandir')
047.517  001.490  000.156: require('CopilotChat.utils')
047.524  001.733  000.225: require('CopilotChat.context')
047.660  000.110  000.110: require('CopilotChat.select')
047.673  002.036  000.166: require('CopilotChat.config')
048.240  000.214  000.214: require('tiktoken_core')
048.243  000.250  000.036: require('CopilotChat.tiktoken')
048.404  000.160  000.160: require('vim.version')
050.236  002.562  002.152: require('CopilotChat.copilot')
050.484  000.042  000.042: require('CopilotChat.ui.overlay')
050.515  000.030  000.030: require('CopilotChat.ui.spinner')
050.517  000.280  000.208: require('CopilotChat.ui.chat')
050.541  000.022  000.022: require('CopilotChat.ui.diff')
050.588  000.047  000.047: require('CopilotChat.ui.debug')
050.592  006.746  000.536: require('CopilotChat')
050.614  000.021  000.021: require('CopilotChat.actions')
050.633  000.018  000.018: require('CopilotChat.integrations.fzflua')

which is similar to something like fzf-lua. The plugin already loads only necessary stuff in setup too.

You could technically move some requires to setup directly, but requires in any other function that is called more than once are unacceptable. I dont rly see a reason to change how default config works either, its fine as is.

[brianhuster]

I use lazy.nvim profile and here is the result

I do use startuptime and here is what I got
250.462 000.076 000.076: sourcing /home/brianhuster/.local/share/nvim/lazy/plenary.nvim/plugin/plenary.vim
252.251 000.083 000.083: require('plenary.tbl')
252.264 000.250 000.167: require('plenary.vararg.rotate')
252.267 000.356 000.106: require('plenary.vararg')
252.591 000.322 000.322: require('plenary.errors')
252.882 000.287 000.287: require('plenary.functional')
252.901 001.133 000.168: require('plenary.async.async')
254.015 000.346 000.346: require('plenary.async.structs')
254.067 000.745 000.400: require('plenary.async.control')
254.096 000.983 000.238: require('plenary.async.util')
254.130 001.226 000.243: require('plenary.async.tests')
254.137 002.702 000.343: require('plenary.async')
255.613 000.573 000.573: require('plenary.bit')
255.724 001.311 000.737: require('plenary.path')
255.833 001.694 000.383: require('plenary.log')
256.024 000.066 000.066: require('CopilotChat.prompts')
256.216 000.048 000.048: require('CopilotChat.notify')
256.508 000.056 000.056: require('plenary.compat')
256.522 000.157 000.101: require('plenary.job')
256.532 000.243 000.086: require('plenary.curl')
256.901 000.366 000.366: require('plenary.scandir')
256.919 000.700 000.091: require('CopilotChat.utils')
256.929 000.902 000.154: require('CopilotChat.context')
257.004 000.073 000.073: require('CopilotChat.select')
257.026 001.190 000.149: require('CopilotChat.config')
257.417 000.254 000.254: require('CopilotChat.tiktoken')
257.500 000.078 000.078: require('vim.version')
261.360 004.332 004.001: require('CopilotChat.copilot')
261.740 000.069 000.069: require('CopilotChat.ui.overlay')
261.798 000.054 000.054: require('CopilotChat.ui.spinner')
261.807 000.439 000.317: require('CopilotChat.ui.chat')
261.861 000.052 000.052: require('CopilotChat.ui.diff')
261.922 000.059 000.059: require('CopilotChat.ui.debug')
261.938 011.379 000.911: require('CopilotChat')
306.017 000.155 000.155: require('vim.treesitter.language')

While it seems low if you take 261.938-250.462, but if you take 306.017-250.462, you get a number similar to what Lazy tells. Moreover, there is no reason vim.treesitter.language can take that much time to load because it is a short file (about 300 LOC) that doesn't require any other modules, so I would rather believe 306.017-261.938 is a part of loading time of CopilotChat.nvim

[deathbeam]

from timing it in my own config, whihc also includes optional fzf lua stuff. Idk, seems fine? could be better i guess but its also nowhere close to 40 times as slow as fzflua for me

[brianhuster]

from timing it in my own config, whihc also includes optional fzf lua stuff. Idk, seems fine? could be better i guess but its also nowhere close to 40 times as slow as fzflua for me

Excuse me, but which tool did you use for that?

[deathbeam]

Literally just put timer on line 12 in my config and then timed it on line 63: https://github.com/deathbeam/dotfiles/blob/master/nvim/.config/nvim/lua/config/copilot.lua#L12