On Thu, Feb 27, 2020 at 07:34:12PM -0800, Matthew Wilcox wrote:

The canonical argument in favour of negative dentries is to improve
application startup time as every application searches the library path
for the same libraries.

The other canonical example is C compilers that need to search for
header files along the include search path:

% strace  -o /tmp/st -f gcc -o /tmp/hello /tmp/hello.c -I.. -I../..
% grep open /tmp/st | grep stdio.h | grep ENOENT | wc -l
6

						- Ted