How to avoid syntax-highlighting for large files in vim?

Question

Huge files take forever to load and work with in vim, due to syntax-highlighting.

I'm looking for a way to limit size of highlighted files, such that files larger than (say) 10MB will be colorless.

score 23 · Accepted Answer · answered Feb 17 '09 at 22:39

23

Adding the following line to _vimrc does the trick, with a bonus: it handles gzipped files, too (which is a common case with huge files):

autocmd BufWinEnter * if line2byte(line("$") + 1) > 1000000 | syntax clear | endif

answered Feb 17 '09 at 22:39

Paul Oyster

You can probably keep your syntax highlighting if you just change `syntax clear` to `syn sync clear`. It's the syncing that slows you down, although YMMV depending on the syntax involved. Personally, I'm editing an 11 million line IDAPro .LST file with no issues after adding that line. – Orwellophile Jul 24 '16 at 00:15
A tip I just discovered to greatly improve the loading time for huge files: disable folding if it has been defined, e.g. `set foldmethod=manual`. – yolenoyer May 14 '20 at 07:20

score 16 · Answer 2 · answered Oct 07 '08 at 15:40

16

Add to your .vimrc:

autocmd BufReadPre * if getfsize(expand("%")) > 10000000 | syntax off | endif

Note that this disables syntax highlighting in ALL buffers; syntax is a global vim thing and cannot be restricted to a single buffer.

answered Oct 07 '08 at 15:40

Zathrus

4

using 'syntax clear' instead of 'syntax off' applies to the one buffer only. – Paul Oyster Nov 24 '08 at 07:03

score 7 · Answer 3 · answered Oct 07 '08 at 12:46

7

I haven't tried it myself, but the LargeFile plugin seems to be exactly to address the kind of stuff you're looking for.

answered Oct 07 '08 at 12:46

tomasr

HS. · Answer 4 · 2008-10-07T13:21:29.643

4

vim -u NONE <filename>

This will skip all initializations from configuration files.

Use uppercase U when running gvim.

"-i NONE" does only exclude viminfo from being loaded. If you defined syntax hilighting in there, that would help too.

edited Oct 07 '08 at 13:21

answered Oct 07 '08 at 13:13

HS.

score 0 · Answer 5 · answered Oct 07 '08 at 13:00

0

vim -c 'syntax off' filename.ext

answered Oct 07 '08 at 13:00

This will switch off highlighting _after_ loading the file. – HS. Oct 07 '08 at 13:15
`vim --cmd 'syntax off'` should run it *before* loading the file. – Orwellophile Jul 24 '16 at 00:20

5 Answers5