Hi Alexei Alexandrov, you wrote:
> Hi Bram et al.,
>
> I'm doing some performance investigations of Vim code trying to understand
> whether there are any possibilities to improve it.
I've also noticed that Vim spends somewhat significant time on startup loading
spell files (I have 2 languages in my .vimrc: set spelllang=en,ru). The time is
mostly spent in EnterCriticalSection/LeaveCriticalSection with getc() upper the
stack. The reason for this is CRT blocking since the runtime is multithreaded.
It's Windows, but on Linux it should be similar.
As far as I understand, Vim doesn't access the spell file from multiple
threads. Thus, the situation can be improved a lot: on Linux by using
getc_unlocked. On Windows, starting VS 2005 there is a function _getc_nolock.
Before VS 2005 this function can be emulated by macro:
#define _getc_nolock(_stream) (--(_stream)->_cnt >= 0 ? \
0xff & *(_stream)->_ptr++ : _filbuf(_stream))
By switching to non-blocking getc() in spell.c I was able to reduce Vim startup
time from about 0.9 seconds to about 0.7 seconds.
--
Alexei Alexandrov
