Slow scrolling in perl files

[r10r]

Hi @wellle,

we experience super slow scrolling in perl files when context.vim is enabled (version c065414)
This happens even in short perl files like /usr/share/vim/vim82/doc/vim2html.pl

Scrolling works perfectly fine with context.vim enabled in other files, e.g in /usr/local/go/src/crypto/elliptic/internal/fiat/p521_fiat64.go with 5k lines.

Maybe related to #68 ?

[r10r]

I've profiled the slow scrolling in /usr/share/vim/vim82/doc/vim2html.pl

context.log

[r10r]

Hmm, I've added let g:context_filetype_blacklist = ['perl'] to my ~/.virmc but scrolling in perl files is still slow.
But when the context.vim plugin is not loaded at all scrolling is back to normal.

[FalcoGer]

I experience something similar with python. It also still happens when context is disabled with :ContextToggle.

Even relatively small python files (63 lines) are dropping a lot of frames when scrolling through them where larger c++ files are just fine. Large python files are extremely slow.

Perhaps context should not update on cursor move or scroll until the cursor stops for some amount of time, say a few hundred milliseconds?

[FalcoGer]

I have disabled the cursormove and winscrolled events and rely on cursorhold for now as a workaround.

[r10r]

Related to #102