In the turnkey core?
in theory with EXT4, the default, you can have an unlimited number of subdirectories and files. The limit is on the entire filesystem.
In reality, it is controlled by the size of the inode table. run 'df -i' to see the inode tables for your specific system. Mine shows:
Filesystem Inodes IUsed IFree IUse% Mounted on
864960 52839 812121 7% /
tmpfs 129302 4 129298 1% /lib/init/rw
udev 128098 494 127604 1% /dev
tmpfs 129302 1 129301 1% /dev/shm
/dev/sda1 124496 207 124289 1% /boot
so you can theoretically have one subdirectory with 864000 files/directories inside it on your system?
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