bug#35531: problem with ls in coreutils

[Viktors Berstis]

I am running coreutlls on Windows, not linux... so strace does not work 
there.

The November 10, 1999 version 3.16 of coreutils "ls" command is 
lightning fast on Windows (and on the large directory) but unfortunately 
stops at 32K files.  The newer version of "ls" built for Windows has the 
problem.
By "new" version, I am using the 64 bit build for windows dated 
4/20/2005 at 11:41AM with exe size of 180736 bytes, md5sum: 
47ba770d80382cbd66ddba13924c1417  Version 5.3.0  .  I didn't see a place 
to download a newer binary version to try.

BTW, booting the machine with Ubuntu, ls on that same large directory is 
very fast.

- Viktors Berstis

Paul Eggert wrote:
> It's probably something inside the kernel (e.g., filesystem code).
>
> What does the shell command 'strace -o /tmp/tr -s 128 -T ls -U -1
> dirname | wc' say? You can see which system calls are taking the most
> time by then running 'sort -t"<" -k2n /tmp/tr'. On my platform (Fedora
> 29 x86-64 ext4, an older desktop with only disk drives), the hoggiest
> syscalls are getdents64, which are as much as 24 ms per call when the
> data are not cached, and more like 0.7 ms per call when the data are
> cached (each such call retrieves about 1000 directory entries). What do
> you see?