linux-ext4 - Re: Re: File limit inside a single directory

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Date:	Sat, 14 Feb 2015 11:17:09 +0100
From:	suntrop@....de
To:	"Eric Sandeen" <sandeen@...hat.com>
Cc:	"Andreas Dilger" <adilger@...ger.ca>,
	"linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>
Subject: Re: Re: File limit inside a single directory

Sorry for confusion, but now I am confused :-) My setup will be like
/files/
/files/1/
/files/2/
/files/3/
(...)
/files/24244/
(...)
/files/113524/

Thus all folders reside within the /files/ directory (can't change that). 
What happens when the max link count reach 32,000 and I create more folders? Will this result in any errors or problems? I’m using ext3. Is the only consequence that the links aren’t counting up any more, like ext4?
 
 

Gesendet: Freitag, 13. Februar 2015 um 18:28 Uhr
Von: "Eric Sandeen" <sandeen@...hat.com>
An: suntrop@....de, "Andreas Dilger" <adilger@...ger.ca>
Cc: "linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>
Betreff: Re: File limit inside a single directory
On 2/13/15 10:49 AM, suntrop@....de wrote:
> Thanks guys. I was afraid of having a couple 100K (at most). The
> server support team told me not to have more than 10 to 20K. There
> seems to be a misconception (for me and people from the CMS) about
> the 32K subdirectory limit, but this ins't for files/folders within a
> single directory but rather nested directories like /1/2/3.../32000

You've confused things a bit here, FWIW.

The 32k (well, 32000 because, sure) limit on ext3 is max link count;
each subdirectory increases the link count on its parent, but only
its parent. It's not about deep nesting, or about files in a dir.
It's only about subdirs in a parent dir.

# mkdir dir
# stat dir | grep Links
Device: fd06h/64774d Inode: 2490391 Links: 2 // . and .. entries
# mkdir dir/subdir1 dir/subdir2 dir/subdir3
# stat dir | grep Links
Device: fd06h/64774d Inode: 2490391 Links: 5
# mkdir dir/subdir1/subsubdir1 dir/subdir1/subsubdir2 dir/subdir1/subsubdir3
# stat dir | grep Links
Device: fd06h/64774d Inode: 2490391 Links: 5

ext4 bumped that max to 64000, and just stops counting if that number
gets exceeded...

-Eric
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