Re: Having ten thousands of mount bind causes various processes to go into loops

[Max Nikulin]

On 12/06/2024 17:02, Julien Petit wrote:
for i in {1..14000}
do
    echo "Mounting dir $i"
    mkdir "/home/test/directories/dir_$i"
    mkdir "/home/test/mounts/dir_$i"
    mount --bind -o rw "/home/test/directories/dir_$i" 
"/home/test/mounts/dir_$i"
done
After that, the "top" command will show processes getting stuck using
100% of CPU never ending.

What processes are CPU hungry?

Has anyone a clue if this is fixable? Should i report a bug?

Perhaps it is not a Debian-specific bug, just more active usage of 
sandboxing in systemd. If some applications have troubles parsing 
/proc/mounts then bugs should be filed against them.

However do you need shared subtrees? It may cause exponential growth of 
number of moutpoints, see
https://docs.kernel.org/filesystems/sharedsubtree.html
https://manpages.debian.org/bookworm/mount/mount.8.en.html#Shared_subtree_operations