Re: ext3_dx_add_entry: Directory index full!

Stefano Fedrigo <[email protected]> Mon, 19 May 2008 01:01:57 +0200
Newsgroups gmane.linux.kernel,gmane.comp.file-systems.ext3.user,gmane.comp.file-systems.ext2.devel
Message-ID <[email protected]>
On May 18, 2008, at 6:24 PM, Theodore Tso wrote:

> No, not a bug, but a limit.  Ext3's hash directores are limited to a
> depth of 3 blocks, which normally isn't a problem if you are using a
> 4k blocksize, since each internal node is small; only 8 bytes.  So you
> have a fanout of 508 for each internal node, and two internal nodes
> gets you to over 250,000 4k directory blocks.  But with a 1k
> blocksize, the internal node fanout is only 124, so that only gets you
> a bit more than 15,000 1k directory blocks.

So, if I understand correctly, with a 1024 bytes blocksize, dir_index,  
and inode size of 128 byte, the maximum number of files in a directory  
is 123008.  With 4k blocks this limit rises to 8,258,048 files?