There is no point in trying to search for files in a directory that
we know does not exist, so stop doing that.
Reduces the total number of stat(2) calls and the number of stat(2)
misses on a medium-sized application by about 21% and 29% respectively.
Reduces the total number of package.json open(2) calls and the number
of open(2) misses by about 21% and 93% (!) respectively.
Before:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
50.93 0.178419 38 4702 lstat
29.08 0.101875 36 2800 2010 stat
11.36 0.039796 43 932 215 open
5.39 0.018897 34 550 fstat
3.24 0.011337 34 336 pread
------ ----------- ----------- --------- --------- ----------------
100.00 0.350324 9320 2225 total
After:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
55.49 0.176638 38 4702 lstat
24.76 0.078826 35 2225 1435 stat
10.19 0.032434 44 733 16 open
6.19 0.019719 36 550 fstat
3.37 0.010723 32 336 pread
------ ----------- ----------- --------- --------- ----------------
100.00 0.318340 8546 1451 total
PR-URL: https://github.com/nodejs/node/pull/9196
Reviewed-By: Brian White <mscdex@mscdex.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Ben Noordhuis
c231130e06