Leaderfbuffer got very slow when some large files open

[zhyzky]

• vim or neovim?
  • vim
  • neovim
• Output of vim --version or nvim --version: 9.0
• Output of :echo has("python"): 0
• Output of :echo has("python3"): 1
• Output of :echo &pythondll(only vim, not neovim):
• Output of :echo &pythonthreedll(only vim, not neovim):
• Output of :py print(sys.version):
• Output of :py3 print(sys.version): 3.10.12
• Output of :echo g:Lf_Debug_Cmd:
• Output of :echo g:Lf_FilesFromCache:
• Operating system:
  • Linux
  • Mac OS X
  • Windows
  • Etc.
• Configurations related to LeaderF in vimrc:
  let g:Lf_ShortcutF = "noexistkey"
  let g:Lf_ShortcutB = "noexistkey"
  let g:Lf_WindowPosition = 'popup'
  let g:Lf_StlSeparator = { 'left': '', 'right': '' }
  let g:Lf_HideHelp = 1
  let g:Lf_UseCache = 0
  let g:Lf_UseVersionControlTool = 0
  let g:Lf_IgnoreCurrentBufferName = 1
  let g:Lf_PreviewInPopup = 1
  let g:Lf_PreviewResult = {'Function': 0, 'BufTag': 0 }
  let g:Lf_WorkingDirectoryMode = 'Ac'

Describe your question, feature request, or bug.

When vim has several large files (>100M) open, the leaderfbuffer got very slow.
It seems this command would excute some file open operation, while the file already loaded.

Steps to reproduce

1. Just load several large files
2. Execute leaderfbuffer and wait

Actual behaviour

The buffer navigation should not be slower than it is inside vim.

Expected behaviour

Somooth navigation between buffers.

[Yggdroot]

yes, because vim's popup window is not so good. Neovim would be faster.

[Yggdroot]

I created an issue vim/vim#15006.

[zhyzky]

yes, because vim's popup window is not so good. Neovim would be faster.

According to vim help, popup_create function allow buffer number being the first parameter. This can speedup the buffer oppenning.
I think the real problerm is when navigate the buffer, getbufline is too slow.

[Yggdroot]

I modified the code that we can only preview 4096 lines. This may speedup the preview.

[zhyzky]

I modified the code that we can only preview 4096 lines. This may speedup the preview.

Thanks for your work. But really little speedup.