Vim verbosefile with timestamps - vim

Question

I have a number of very long and complex Vim configuration files, but these seem to be causing some unpredictable performance slowdowns.
Is there a way of producing a logfile of Vim's internal activity (in the style of verbosefile) which also includes timestamps for each function call to allow me to debug these issues. Alternatively, are there any other tools to help me in this task?

Answer 1

One thing you can try is invoking vim with --startuptime some_file. This will dump the steps performed during startup, along with timestamps. Try :help --startuptime for some more information.
Unfortunately, this shows you timestamps for files, not functions. If you want to see how long a specific function takes, you could put a call to it in a file under the plugin directory, so it's executed on boot. This won't be possible in all cases and it won't give you a lot of granularity, but it might help you narrow down the problem. Someone else might have a better idea, but I'd start by trying something like this.
EDIT:
I just found two things that may help with this problem. One of them is reltime(). Here's an example from vim's help:
let start = reltime()
call MyFunction()
echo reltimestr(reltime(start))
All it does is show the time a function takes to execute. Combined with, for example, Decho, this could provide a simple log of said functions.
The second one should be a lot more powerfule, the :profile command. It lets you profile a piece of vimscript and place the results in a file. :help profile should tell you all you need to know. Unfortunately, it's only available with the +profile feature, which seems to be enabled only in the "huge" feature set. If your vim doesn't have it, you'll need to recompile. If that's a problem, or you don't want to bother, you might be able to achieve good results with reltime alone.

Answer 2

If --startuptime does not fit your needs, you may use the following command:
vim --cmd 'profile start profile.log' \
--cmd 'profile func *' \
--cmd 'profile file *' \
-c 'profile pause' \
-c 'qa!'
(replace --cmd with -c and add -c 'Command that causes slowdown' if problem occurs not at startup). You will get all timings in the profile.log. Table with function timings will be present at the end of the file, to get per-script timings, use the following
script:
" Open profile.log file in vim first
let timings=[]
g/^SCRIPT/call add(timings, [getline('.')[len('SCRIPT '):], matchstr(getline(line('.')+1), '^Sourced \zs\d\+')]+map(getline(line('.')+2, line('.')+3), 'matchstr(v:val, ''\d\+\.\d\+$'')'))
enew
call setline('.', ['count total (s) self (s) script']+map(copy(timings), 'printf("%5u %9s %8s %s", v:val[1], v:val[2], v:val[3], v:val[0])'))
This will open a new file containing just the same table as at the end of profile.log, but 1) for scripts, not for functions, 2) unsorted.

Answer 3

Better late than never? I was searching to see if I could get vim to include some timestamps in the &verbosefile, as it causes vim to append to the file with no indication of when the appending started.
I adapted the solution from ZyX's answer here and after trying some things out, found that a simple echo "foo\n" will append foo and a newline to the &verbosefile:
let s:VerboseLS = ' **** V'.'E'.'RB'.'OSE LO'.'GG'.'ING S'.'TA'.'RTED ****'
let s:VerboseLE = ' **** V'.'E'.'RB'.'OSE LO'.'GG'.'ING E'.'ND'.'ED ****'
function! ToggleVerbose()
let l:timestamp = strftime("%c")
if !&verbose
let l:msg = "\n\n" . l:timestamp . s:VerboseLS . "\n\n"
set verbosefile=~/.vim/log/verbose.log
set verbose=100
echo l:msg
else
let l:msg = "\n" . l:timestamp . s:VerboseLE . "\n"
echo l:msg
set verbose=0
set verbosefile=
endif
endfunction
nnoremap <silent> <Leader>vl :call ToggleVerbose()<CR>
Now I get nice banners in my log:
Sun Feb 17 14:18:02 2013 **** VERBOSE LOGGING STARTED ****
...[snip]...
Sun Feb 17 14:18:08 2013 **** VERBOSE LOGGING ENDED ****
I defined those banners the way I did so that if I source that script file while verbose logging is on so if I search the log for "VERBOSE LOGGING" or similar I won't match on them.
So, you could adapt this method to use reltime if your vim has('reltime') for sub-second precision and maybe make a timing wrapper to call that echos the start/end times for function calls (although you'd have to refactor when you call things inline without the call command).
Ooh, I just had an idea... I wonder if &verbosefile can be set to a named pipe that goes to util that prepends time stamps... Let's see...