posix: don't compare atime when determining if a file has changed
A file's atime might change even if the file itself doesn't change. This might
cause us to invalidate caches more often than necessary.
Before this change, hg add often resulted in the dirstate being parsed twice
on systems that track atime. After this change, it is only parsed once. For a
repository with over 180,000 files, this speeds up hg add from 1.2 seconds to
1.0.
$ "$TESTDIR/hghave" inotify || exit 80
$ hg init
$ touch a b c d e f
$ echo "[extensions]" >> $HGRCPATH
$ echo "inotify=" >> $HGRCPATH
inserve
$ hg inserve -d --pid-file=hg.pid 2>&1
$ cat hg.pid >> "$DAEMON_PIDS"
$ hg ci -Am m
adding a
adding b
adding c
adding d
adding e
adding f
adding hg.pid
let the daemon finish its stuff
$ sleep 1
eed to test all file operations
$ hg rm a
$ rm b
$ echo c >> c
$ touch g
$ hg add g
$ hg mv e h
$ hg status
M c
A g
A h
R a
R e
! b
$ sleep 1
Are we able to kill the service? if not, the service died on some error
$ kill `cat hg.pid`