High CPU usage

[petobens]

I recently noticed that my computer becomes slow when editing files with Vim and I think the problem might be with neocomplete. In the following gif you will see that if I start Vim with a minimal vimrc (attached after the GIF), open that vimrc file and get into insert mode then my CPU usage increases to more than 30%. I'm using Kaoriya GVIM 64-bit version (227 patches) and I build vimproc with MinGW64.

This is the minimal vimrc:

set nocompatible

set runtimepath+=~/vimfiles/bundle/neocomplete/
set runtimepath+=~/vimfiles/bundle/vimproc/

let g:neocomplete#enable_at_startup = 1

if !exists('g:neocomplete#keyword_patterns')
    let g:neocomplete#keyword_patterns = {}
endif
let g:neocomplete#keyword_patterns._ = '^\\\?\h\w*$'
let keyword_patterns = {}
let keyword_patterns = {'tex' : '\h\w*:\%(\w*_\w*\)\?'}
call neocomplete#custom#source('buffer', 'keyword_patterns',
        \ keyword_patterns)

I did some profiling which you can download here

[Shougo]

It is feature. Unfortunatelly, in Windows environment, Vim is slow.
I cannot fix it.

[Shougo]

You can initialize neocomplete when starting.

call neocomplete#initialize()

[petobens]

So your recommendation is to have the following in my vimrc?

if neobundle#is_sourced('neocomplete')
    call neocomplete#initialize()
endif

and remove:

let g:neocomplete#enable_at_startup = 1

Or what is the proper way to do it? The docs say:

Note: You should call it in VimEnter autocmd.
User customization for neocomplete must be set before
initialization of neocomplete.

So neocomplete#initialize() should be called at the end of all my necomplete settings? If I call it before my necomplete settings then the cpu usage problem disappears (but my settings are losts) but if I call it at the end then the problem persists.

I'm pretty sure that the problem is not a Vim issue but a neocomplete issue related with the following three lines:

let keyword_patterns = {}
let keyword_patterns = {'tex' : '\h\w*:\%(\w*_\w*\)\?'}
call neocomplete#custom#source('buffer', 'keyword_patterns',
        \ keyword_patterns)

And in particular with the last line (that calls the function): if I remove it
then everything works great (but I need it!). The strange thing I noticed is
that the high CPU usage is present in every filetype except in tex files! I
really hope you can help me. Thanks in advance.

[Shougo]

Sorry, I cannot help you. I think it is initialize feature.
You can check the neocomplete code.
Because, it is open source.

[petobens]

I did some more testing and apparently specifying a default pattern seems to fix the problem:

let keyword_patterns = {}
let keyword_patterns = {
        \ 'default' : '\h\w*',
        \ 'tex' : '\h\w*:\%(\w*_\w*\)\?'
        \ }
call neocomplete#custom#source('buffer', 'keyword_patterns',
            \ keyword_patterns)

However I don't understand why this seems to fix it.

[Shougo]

In default, neocomplete uses keyword pattern(\k\+). It is slower than \h\w*.

[petobens]

So neocomplete's default pattern for buffer source is \k\+? Where can I see that part of the code? I cannot find it. I ask this because I have a similar setting for the dictionary source:

let keyword_patterns2 = {'tex' : '\\\?\h\w*'}
call neocomplete#custom#source('dictionary', 'keyword_patterns',
        \ keyword_patterns2)

but in the case of dictionary there is no CPU usage problem and no need to specify a default pattern.

[Shougo]

It is from g:neocomplete#keyword_patterns['default'].
I may change this default value.

[petobens]

Thanks for the reply. I see that you finally changed the default pattern. My problem however seems to be with neocomplete-source-attribute-keyword_patterns. In the docs it says:

This attribute is optional; if it is not given,
|g:neocomplete#keyword_patterns| is used as the
default value.

However if I don't add default key in keyword_patterns dictionary then my problem appears:

let keyword_patterns = {}
let keyword_patterns = {
        \ 'default' : '\h\w*',
        \ 'tex' : '\h\w*:\%(\w*_\w*\)\?'
        \ }
call neocomplete#custom#source('buffer', 'keyword_patterns',
        \ keyword_patterns)

[Shougo]

However if I don't add default key in keyword_patterns dictionary then my problem appears:

Is it latest version?
I don't know why...

[petobens]

I'm using the latest version. If I don't add default key in keyword_patterns dictionary and then call the command :echo neocomplete#get_keyword_pattern('_','buffer') and empty string is returned. Shouldn't that command return \h\w* ? The problem seems to appear when one specifies custom-source-attribute-keyword_patterns because, for instance, if I don't include:

let keyword_patterns2 = {'tex' : '\\\?\h\w*'}
call neocomplete#custom#source('dictionary', 'keyword_patterns',
        \ keyword_patterns2)

then the command :echo neocomplete#get_keyword_pattern('_','dictionary') correctly returns \h\w*. However if I include those lines and call the same command then it returns and empty string.

[Shougo]

OK, I fixed it.

[petobens]

Thanks Shougo. I have one more question. If, for instance, if I don't include:

let keyword_patterns2 = {'tex' : '\\\?\h\w*'}
call neocomplete#custom#source('dictionary', 'keyword_patterns',
        \ keyword_patterns2)

then the command :echo neocomplete#get_keyword_pattern('python','dictionary') returns [@]\?\h\w*. However if I include those lines and call the same command now it returns \h\w*. Since I'm not specifying a python key in keyword_patterns2 dictionary why is it returning \h\w* instead of [@]\?\h\w* ?

[Shougo]

Yes, it is feature. Because call neocomplete#custom#source('dictionary', 'keyword_patterns' overwrites default keyword pattern.
You must add patterns manually if needed.
I may add easy way to append default patterns in neocomplete.

[petobens]

Ahhh okok. However I think this is not a good feature. I think that neocomplete#custom#source('dictionary', 'keyword_patterns', 'keyword_patterns2') should overwrite patterns only for the filetypes that are defined in the keyword_patterns2 dictionary (in my example only for tex files and leave all other filetypes (such as python) in their default init values).

[petobens]

Hello Shougo. Have you had a chance to read and reconsider what I said in my last comment? Thanks in advance.

[Shougo]

Yes, I know your comment. I can implement it. But I have not much time.

[petobens]

Thanks! No need to hurry at all. I was just wondering if you had read it.