linux-kernel - Re: ext3/ext4 directories don't shrink after deleting lots of files

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <605A8D56-81CD-4775-8FCD-58CDB12CBA36@iki.fi>
Date:	Thu, 14 May 2009 20:45:38 -0400
From:	Timo Sirainen <tss@....fi>
To:	Josef Bacik <josef@...icpanda.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: ext3/ext4 directories don't shrink after deleting lots of files

On May 14, 2009, at 8:32 PM, Josef Bacik wrote:

> On Thu, May 14, 2009 at 6:02 PM, Timo Sirainen <tss@....fi> wrote:
>> I've noticed that if you create e.g. 100k files to a directory and  
>> then
>> delete the files, the directory entry still seems to take a couple of
>> megabytes. Later whenever accessing the (almost empty) directory it  
>> can
>> take a few seconds to load it into cache.
>>
>> Is there a way to shrink the directory somehow without having to  
>> rmdir()
>> it? Would be nice if kernel did it automatically, but I could live  
>> with
>> a manual userspace syscall/tool as well.
>>
>
> fsck -D <device>, when its unmounted of course.

I was rather thinking something that I could run while the system was  
fully operational. Otherwise just moving the files to a temp directory  
+ rmdir() + rename() would have been fine too.

I just tested that xfs, jfs and reiserfs all shrink the directories  
immediately. Is it more difficult to implement for ext* or has no one  
else found this to be a problem?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/