linux-ext4 - Re: getdents - ext4 vs btrfs performance

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]

Date:	Thu, 1 Mar 2012 15:43:41 +0100
From:	Jacek Luczak <difrost.kernel@...il.com>
To:	Chris Mason <chris.mason@...cle.com>,
	Jacek Luczak <difrost.kernel@...il.com>,
	Hillf Danton <dhillf@...il.com>, linux-ext4@...r.kernel.org,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>, linux-btrfs@...r.kernel.org,
	lczerner@...hat.com
Subject: Re: getdents - ext4 vs btrfs performance

2012/3/1 Chris Mason <chris.mason@...cle.com>:
> On Thu, Mar 01, 2012 at 03:03:53PM +0100, Jacek Luczak wrote:
>> 2012/3/1 Hillf Danton <dhillf@...il.com>:
>> > On Thu, Mar 1, 2012 at 9:35 PM, Jacek Luczak <difrost.kernel@...il.com> wrote:
>> >>
>> >> While I was about to grab acp I've noticed seekwatcher with made my day :)
>> >>
>> >> seekwatcher run of tar cf to eliminate writes (all done on 3.2.7):
>> >> 1) btrfs: http://dozzie.jarowit.net/~dozzie/luczajac/tar_btrfs.png
>> >> 2) ext4: http://dozzie.jarowit.net/~dozzie/luczajac/tar_ext4.png
>> >> 3) both merged: http://dozzie.jarowit.net/~dozzie/luczajac/tar_btrfs_ext4.png
>
> Whoa, seekwatcher makes it pretty clear.

Yep, ext4 is close to my wife's closet.

>> >>
>> >> I will send acp results soon.
>> >>
>> > Would you please take reiserfs into account?
>>
>> As of now not (lack of time) but I'm pretty close to consider XFS in
>> the game. Whenever I will have more time and there won't be a pressure
>> on giving host back to production I will redo same tests for reiserfs.
>>
>> Now I'm focused on the userspace sorting results.
>
> reiserfs should have results very similar to ext4.  The directory
> hashing used by reiserfs is going to result in a very random read
> pattern.
>
> XFS will probably beat btrfs in this test.  Their directory indexes
> reflect on disk layout very well.

True, but not that fast on small files.

Except the question I've raised in first mail there's a point in all
those action. We are maintaining host that are used for building
software: random access, lot of small files and dirs (always a co),
heavy parallel IO. We were testing XFS vs ext4 a year ago and XFS was
around 10% slower on build times. We did not - yet - done same on
btrfs. Now we're looking for replacement for ext4 as we suffer from
those issue - but we were not aware of that until stepped into this
issue.

If you would like me to do some specific tests around ext4 and btrfs,
let me know.

-Jacek
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html