linux-kernel - Re: Linux mdadm superblock question.

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: <alpine.DEB.2.00.1002171040350.4721@asgard.lang.hm>
Date:	Wed, 17 Feb 2010 10:41:34 -0800 (PST)
From:	david@...g.hm
To:	Nick Bowler <nbowler@...iptictech.com>
cc:	Volker Armin Hemmann <volkerarmin@...glemail.com>,
	Kyle Moffett <kyle@...fetthome.net>,
	Rudy Zijlstra <rudy@...mpydevil.homelinux.org>,
	Neil Brown <neilb@...e.de>,
	"Mr. James W. Laferriere" <babydr@...y-dragons.com>,
	Bill Davidsen <davidsen@....com>,
	Michael Evans <mjevans1983@...il.com>,
	linux-kernel@...r.kernel.org, linux-raid@...r.kernel.org
Subject: Re: Linux mdadm superblock question.

On Wed, 17 Feb 2010, Nick Bowler wrote:

> On 19:27 Wed 17 Feb     , Volker Armin Hemmann wrote:
>> On Mittwoch 17 Februar 2010, Nick Bowler wrote:
>>> On 09:41 Wed 17 Feb     , david@...g.hm wrote:
>>>> for a distro that is trying to make one kernel image run on every
>>>> possible type of hardware features like initramfs (and udev, modeules,
>>>> etc) are wonderful.
>>>>
>>>> however for people who run systems that are known ahead of time and
>>>> static (and who build their own kernels instead of just relying on the
>>>> distro default kernel), all of this is unnessesary complication, which
>>>> leaves more room for problems to creep in.
>>>
>>> Such people can easily construct an initramfs containing busybox and
>>> mdadm with a shell script hardcoded to mount their root fs and run
>>> switch_root.  It's a ~10 minute jobbie that only needs to be done once.
>>
>> and even better when you don't have to do that one time job at all.
>
> But people who are building their own kernels are already doing a
> (much harder, imo) one time job of configuring their kernels.
>
>> btw, what about additional delay?
>
> It takes about half a second for mdadm to assemble my root array, is
> that what you're referring to?
>
> I assume that kernel auto-assembly is no faster, although I've never
> used it.  Regardless, half a second isn't very long to wait.

If you are aiming for a 5-second boot time it's 10% of your total boot 
time. That's a lot for a feature that's not needed.

David Lang
--
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/