From: Eric Sandeen <sandeen@redhat.com>
Subject: Re: [PATCH v3 0/2] ext4: increase mbcache scalability
Date: Wed, 18 Sep 2013 09:19:10 -0500
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Cc: "Theodore Ts'o" <tytso@mit.edu>,
	Andreas Dilger <adilger@dilger.ca>,
	T Makphaibulchoke <tmac@hp.com>,
	"linux-ext4@vger.kernel.org List" <linux-ext4@vger.kernel.org>,
	aswin@hp.com, aswin_proj@lists.hp.com
To: Thavatchai Makphaibulchoke <thavatchai.makpahibulchoke@hp.com>
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On 9/17/13 11:43 AM, Thavatchai Makphaibulchoke wrote:
> On 09/13/2013 12:59 PM, Eric Sandeen wrote:
>> 
>> suggestions:
>> 
>> 1) send us dumpe2fs -h /dev/sdXX | grep "Inode size" for this
>> filesystem 2) print out the inode number in your printk's above 3)
>> stat one of those inodes in debugfs after the run (debugfs stat
>> <inodenumber>) - with <> around the inode nr
>> 
>> -Eric
>> 
> 
> I think I found out why we get into the mbcache path.  The test uses
> ramfss, which are mounted and unmounted at the start and end of the
> test.  Looks like a ramfs' default inode size is 128, causing all the
> mbcaching for the xattrs.  There seems to be nothing wrong with
> either SELinux or xattr.  Sorry for the confusion.

smaller filesystems go back to 128 byte inodes, IIRC.

That's why I asked for dumpe2fs long ago ;)

But glad to have the mystery solved!

Thanks,
-Eric

> Thanks, Mak.
>