You can put the unlimited number of files and subdirectories under a directory which formatted using ext4 file system.
Unlimited number of subdirectories in the ext4 file system
Ext4 allows an unlimited number of subdirectories. (In ext3 a directory can have at most 32,000 subdirectories.). To allow for larger directories and continued performance, ext4 turns on HTree indices (a specialized version of a B-tree) by default. This feature is implemented in Linux 2.6.23 kernel. In ext3 HTrees can be used by enabling the dir_index feature.
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Use df -i to see the number of inodes
The maximum number of files is global, not per directory, and it’s determined by the number of inodes allocated when the filesystem was created. Try running the following command to see the number of inodes per filesystem
[root@dbappweb ~]# df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/sda10 2621440 96759 2524681 4% / /dev/mapper/mpathgp1 201326592 6668892 194657700 4% /upload
Last Updated: Apr 11, 2018