[gentoo-user] ext4/ext3 for /boot?

[gentoo-user] ext4/ext3 for /boot?

[Jarry]

Hi,
just out of curiosity: is it possible to use ext4/ext3
filesystem even for separate /boot partition?

For /boot I'm still using ext2, but a friend of mine
is just doing installation and asked me what filesystem
he should use, so I told him not to complicate things
and simply use ext4 for all. But now I'm not so sure if he
is able to boot his new fresh gentoo-system at the end?

Jarry
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Re: [gentoo-user] ext4/ext3 for /boot?

[Stéphane Guedon]

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On Monday 07 November 2011 19:29:06 Jarry wrote:
> Hi,
> just out of curiosity: is it possible to use ext4/ext3
> filesystem even for separate /boot partition?
> 
> For /boot I'm still using ext2, but a friend of mine
> is just doing installation and asked me what filesystem
> he should use, so I told him not to complicate things
> and simply use ext4 for all. But now I'm not so sure if he
> is able to boot his new fresh gentoo-system at the end?
> 
> Jarry

I use ext4 as /, with a boot directory (so my / is /boot).
Don't worry !

-- 
Stéphane Guedon
page web : http://www.22decembre.eu/
carte de visite : http://www.22decembre.eu/downloads/Stephane-Guedon.vcf
clé publique gpg : http://www.22decembre.eu/downloads/Stephane-Guedon.asc

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Re: [gentoo-user] ext4/ext3 for /boot?

[Alan McKinnon]

On Mon, 07 Nov 2011 19:29:06 +0100
Jarry <mr.jarry@gmail.com> wrote:

> Hi,
> just out of curiosity: is it possible to use ext4/ext3
> filesystem even for separate /boot partition?

Yes.

ext2/3/4 are all backwards compatible. ext4 does have a certain feature
(I forget what) that once used breaks this compatibility but you are
highly, highly unlikely to ever do that on /boot.

The benefits of ext3/4 are irrelevant for /boot anyway - that
filesystem is write-seldom, read ever so slightly more often.



> For /boot I'm still using ext2, but a friend of mine
> is just doing installation and asked me what filesystem
> he should use, so I told him not to complicate things
> and simply use ext4 for all. But now I'm not so sure if he
> is able to boot his new fresh gentoo-system at the end?
> 
> Jarry



-- 
Alan McKinnnon
alan.mckinnon@gmail.com

Re: [gentoo-user] ext4/ext3 for /boot?

[Michael Mol]

On Mon, Nov 7, 2011 at 2:26 PM, Alan McKinnon <alan.mckinnon@gmail.com> wrote:
> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
> (I forget what) that once used breaks this compatibility but you are
> highly, highly unlikely to ever do that on /boot.

"Extents," I believe. But I don't know exactly what that means, or
when it comes into play.

> The benefits of ext3/4 are irrelevant for /boot anyway - that
> filesystem is write-seldom, read ever so slightly more often.

Well, there's ext4's "high water" mark, which reduces fsck time...but
/boot is generally small enough that fsck time is negligible.

-- 
:wq

[gentoo-user] Re: ext4/ext3 for /boot?

[Nikos Chantziaras]

On 11/07/2011 09:32 PM, Michael Mol wrote:
> On Mon, Nov 7, 2011 at 2:26 PM, Alan McKinnon<alan.mckinnon@gmail.com>  wrote:
>> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
>> (I forget what) that once used breaks this compatibility but you are
>> highly, highly unlikely to ever do that on /boot.
>
> "Extents," I believe. But I don't know exactly what that means, or
> when it comes into play.

Works just fine with extents too.  At least Grub as included in Portage 
(it contains patches that add support for ext4.)

Re: [gentoo-user] ext4/ext3 for /boot?

[Stroller]

On 7 November 2011, at 19:32, Michael Mol wrote:

> On Mon, Nov 7, 2011 at 2:26 PM, Alan McKinnon <alan.mckinnon@gmail.com> wrote:
>> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
>> (I forget what) that once used breaks this compatibility but you are
>> highly, highly unlikely to ever do that on /boot.
> 
> "Extents," I believe. But I don't know exactly what that means, or
> when it comes into play.

It means, as a huge simplification, that ext4 can allocate a file to blocks 1234 - 1256, instead of having to separately allocate blocks 1234, 1235, 1236, 1237, 1238, 1239, 1240, and so on (as ext3 would have had to do).

This fixes ext3's "slow deletes" problem, because only a single entry in the allocation table needs to be removed, instead of many. If you delete a big file (say a 9gig DVD or 40gig blu-ray .iso image file) it's at least an order of magnitude slower on ext3 than it is on ext4.

As I said, this is a huge simplification, and I'm sure there are folks who would take pleasure in explaining how wrong it is, but it's a good enough explanation for a couple of sentences that you can easily grasp. For more details the "Features - Extents" section of ext4's wikipedia page [1] and this other article [2] (these are top hits on Google for "ext4 extents") look pretty good.

Stroller.




[1] http://en.wikipedia.org/wiki/Ext4#Features
[2] http://computer-forensics.sans.org/blog/2011/03/28/digital-forensics-understanding-ext4-part-3-extent-trees

Re: [gentoo-user] ext4/ext3 for /boot?

[Michael Mol]

On Mon, Nov 7, 2011 at 3:42 PM, Stroller <stroller@stellar.eclipse.co.uk> wrote:
> On 7 November 2011, at 19:32, Michael Mol wrote:
>> On Mon, Nov 7, 2011 at 2:26 PM, Alan McKinnon <alan.mckinnon@gmail.com> wrote:
>>> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
>>> (I forget what) that once used breaks this compatibility but you are
>>> highly, highly unlikely to ever do that on /boot.
>>
>> "Extents," I believe. But I don't know exactly what that means, or
>> when it comes into play.
>
> It means, as a huge simplification, that ext4 can allocate a file to blocks 1234 - 1256, instead of having to separately allocate blocks 1234, 1235, 1236, 1237, 1238, 1239, 1240, and so on (as ext3 would have had to do).
>
> This fixes ext3's "slow deletes" problem, because only a single entry in the allocation table needs to be removed, instead of many. If you delete a big file (say a 9gig DVD or 40gig blu-ray .iso image file) it's at least an order of magnitude slower on ext3 than it is on ext4.
>
> As I said, this is a huge simplification, and I'm sure there are folks who would take pleasure in explaining how wrong it is, but it's a good enough explanation for a couple of sentences that you can easily grasp. For more details the "Features - Extents" section of ext4's wikipedia page [1] and this other article [2] (these are top hits on Google for "ext4 extents") look pretty good.
>
> Stroller.
>
> [1] http://en.wikipedia.org/wiki/Ext4#Features
> [2] http://computer-forensics.sans.org/blog/2011/03/28/digital-forensics-understanding-ext4-part-3-extent-trees

Very, very nice reads. Thanks.


-- 
:wq

Re: [gentoo-user] ext4/ext3 for /boot?

[Alan Mackenzie]

On Mon, Nov 07, 2011 at 09:26:50PM +0200, Alan McKinnon wrote:

> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
> (I forget what) that once used breaks this compatibility but you are
> highly, highly unlikely to ever do that on /boot.

> The benefits of ext3/4 are irrelevant for /boot anyway - that
> filesystem is write-seldom, read ever so slightly more often.

Really?  I put my PC into power saving mode before going to bed each
evening.  The PC needs to read /boot to return to normal operation.

> -- 
> Alan McKinnnon
> alan.mckinnon@gmail.com

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: [gentoo-user] ext4/ext3 for /boot?

[Dale]

Alan Mackenzie wrote:
> On Mon, Nov 07, 2011 at 09:26:50PM +0200, Alan McKinnon wrote:
>
>> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
>> (I forget what) that once used breaks this compatibility but you are
>> highly, highly unlikely to ever do that on /boot.
>> The benefits of ext3/4 are irrelevant for /boot anyway - that
>> filesystem is write-seldom, read ever so slightly more often.
> Really?  I put my PC into power saving mode before going to bed each
> evening.  The PC needs to read /boot to return to normal operation.
>
>> -- 
>> Alan McKinnnon
>> alan.mckinnon@gmail.com

Really.  It takes maybe 1/4 of a second for it to load the kernel from 
/boot.  After that, it may not read /boot again until you boot back up 
the next day.  So, 1/4 of a second per boot is very little.  The only 
other time /boot is used is when you update grub or your kernel.  That 
is maybe a 1 or 2 second write, if that much.  Even if you 
hibernate/sleep/reboot a few times a day, it is still read very little.  
That is pretty much irrelevant.

Me, I have always put ext2 on /boot.  I just don't see much need in 
anything fancy for something that is used so seldom plus everything is 
likely stored somewhere else anyway.  The kernel should be in the kernel 
source directory and a emerge of grub would restore everything else 
except the config.  Not much to lose there.

< shrugs >

Dale

:-)  :-)

Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

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On Nov 8, 2011 5:03 PM, "Dale" <rdalek1967@gmail.com> wrote:
>
> Alan Mackenzie wrote:
>>
>> On Mon, Nov 07, 2011 at 09:26:50PM +0200, Alan McKinnon wrote:
>>
>>> ext2/3/4 are all backwards compatible. ext4 does have a certain feature
>>> (I forget what) that once used breaks this compatibility but you are
>>> highly, highly unlikely to ever do that on /boot.
>>> The benefits of ext3/4 are irrelevant for /boot anyway - that
>>> filesystem is write-seldom, read ever so slightly more often.
>>
>> Really?  I put my PC into power saving mode before going to bed each
>> evening.  The PC needs to read /boot to return to normal operation.
>>
>>> --
>>> Alan McKinnnon
>>> alan.mckinnon@gmail.com
>
>
> Really.  It takes maybe 1/4 of a second for it to load the kernel from
/boot.  After that, it may not read /boot again until you boot back up the
next day.  So, 1/4 of a second per boot is very little.  The only other
time /boot is used is when you update grub or your kernel.  That is maybe a
1 or 2 second write, if that much.  Even if you hibernate/sleep/reboot a
few times a day, it is still read very little.  That is pretty much
irrelevant.
>
> Me, I have always put ext2 on /boot.  I just don't see much need in
anything fancy for something that is used so seldom plus everything is
likely stored somewhere else anyway.  The kernel should be in the kernel
source directory and a emerge of grub would restore everything else except
the config.  Not much to lose there.
>

Not to mention that /boot usually has a noauto option, so it's very
unlikely that a wayward prog can somehow bollix up the filesystem.

In addition, if one's using ext4, the in-kernel ext4 fs driver performs
perfectly well as an ext2/3 driver.

Rgds,

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Re: [gentoo-user] ext4/ext3 for /boot?

[Neil Bothwick]

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On Tue, 8 Nov 2011 18:15:06 +0700, Pandu Poluan wrote:

> > Me, I have always put ext2 on /boot.  I just don't see much need in  
> > anything fancy for something that is used so seldom plus everything is
> > likely stored somewhere else anyway.  The kernel should be in the
> > kernel source directory and a emerge of grub would restore everything
> > else except the config.  Not much to lose there.

One of the benefits of GRUB2 is that the information used to create the
config file is in /etc. If /boot is toasted, you can recreate all you
need with

grub2-install
grub2-mkconfig
cd /usr/src/linux
make install

> Not to mention that /boot usually has a noauto option, so it's very
> unlikely that a wayward prog can somehow bollix up the filesystem.

Leaving /boot unmounted invites the inevitable error of forgetting to
mount it before installing a new kernel. I prefer to mount it ro, that
way its contents are available, protected from accidental overwriting and
it shouts at you if you forget to remount it before installing a kernel
or updating GRUB.


-- 
Neil Bothwick

But I thought YOU did the backups...

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Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

On Tue, Nov 8, 2011 at 19:35, Neil Bothwick <neil@digimed.co.uk> wrote:
> On Tue, 8 Nov 2011 18:15:06 +0700, Pandu Poluan wrote:
>
>> > Me, I have always put ext2 on /boot.  I just don't see much need in
>> > anything fancy for something that is used so seldom plus everything is
>> > likely stored somewhere else anyway.  The kernel should be in the
>> > kernel source directory and a emerge of grub would restore everything
>> > else except the config.  Not much to lose there.
>
> One of the benefits of GRUB2 is that the information used to create the
> config file is in /etc. If /boot is toasted, you can recreate all you
> need with
>
> grub2-install
> grub2-mkconfig
> cd /usr/src/linux
> make install
>
>> Not to mention that /boot usually has a noauto option, so it's very
>> unlikely that a wayward prog can somehow bollix up the filesystem.
>
> Leaving /boot unmounted invites the inevitable error of forgetting to
> mount it before installing a new kernel. I prefer to mount it ro, that
> way its contents are available, protected from accidental overwriting and
> it shouts at you if you forget to remount it before installing a kernel
> or updating GRUB.
>

I have a script that does the menuconfig + diff .config + make +
install (including kernel copying to /boot, automagically mounting
/boot if needed), so I can get away with noauto ;-)

Oh, and it also auto-modifies grub.cfg for me :-D

Rgds,
-- 
FdS Pandu E Poluan
~ IT Optimizer ~

 • LOPSA Member #15248
 • Blog : http://pepoluan.tumblr.com
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Re: [gentoo-user] ext4/ext3 for /boot?

[Dale]

Pandu Poluan wrote:
> I have a script that does the menuconfig + diff .config + make + 
> install (including kernel copying to /boot, automagically mounting 
> /boot if needed), so I can get away with noauto ;-) Oh, and it also 
> auto-modifies grub.cfg for me :-D Rgds, 

Smarty pants.  :-P

Dale

:-)  :-)

Re: [gentoo-user] ext4/ext3 for /boot?

[Sebastian Beßler]

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Am 08.11.2011 14:11, schrieb Pandu Poluan:

> Oh, and it also auto-modifies grub.cfg for me :-D


Why modify grub.cfg?

I have symlinks in /boot

vmlinuz -> vmlinuz-3.1.0-gentoo
and
vmlinuz.old -> vmlinuz-3.1.0-rc6-00105-g279b1e0

who automagic get updated when ever I run make install.

The corresponding part of grub.conf is

title Gentoo Linux (OpenRC)
        root (hd0,1)
        kernel /vmlinuz root=/dev/sda3 radeon.agpmode=-1
video=radeon:1440x900 zcache

and

title Gentoo Linux.old (OpenRC)
        root (hd0,1)
        kernel /vmlinuz.old root=/dev/sda3 radeon.agpmode=-1
video=radeon:1440x900 zcache

That is all, no changing grub.conf and always the latest kernel.

Greetings

Sebastian


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Re: [gentoo-user] ext4/ext3 for /boot?

[Paul Hartman]

On Tue, Nov 8, 2011 at 3:59 PM, Sebastian Beßler
<sebastian@darkmetatron.de> wrote:
> Am 08.11.2011 14:11, schrieb Pandu Poluan:
>
>> Oh, and it also auto-modifies grub.cfg for me :-D
>
>
> Why modify grub.cfg?
>
> I have symlinks in /boot
>
> vmlinuz -> vmlinuz-3.1.0-gentoo
> and
> vmlinuz.old -> vmlinuz-3.1.0-rc6-00105-g279b1e0
>
> who automagic get updated when ever I run make install.
>
> The corresponding part of grub.conf is
>
> title Gentoo Linux (OpenRC)
>        root (hd0,1)
>        kernel /vmlinuz root=/dev/sda3 radeon.agpmode=-1
> video=radeon:1440x900 zcache
>
> and
>
> title Gentoo Linux.old (OpenRC)
>        root (hd0,1)
>        kernel /vmlinuz.old root=/dev/sda3 radeon.agpmode=-1
> video=radeon:1440x900 zcache
>
> That is all, no changing grub.conf and always the latest kernel.

I've used the same method as you "forever" and it works great, and
always easy fail-safe to boot previous kernel in case I got something
wrong on the new one.

Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

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On Nov 9, 2011 6:03 AM, "Paul Hartman" <paul.hartman+gentoo@gmail.com>
wrote:
>
> On Tue, Nov 8, 2011 at 3:59 PM, Sebastian Beßler
> <sebastian@darkmetatron.de> wrote:
> > Am 08.11.2011 14:11, schrieb Pandu Poluan:
> >
> >> Oh, and it also auto-modifies grub.cfg for me :-D
> >
> >
> > Why modify grub.cfg?
> >
> > I have symlinks in /boot
> >
> > vmlinuz -> vmlinuz-3.1.0-gentoo
> > and
> > vmlinuz.old -> vmlinuz-3.1.0-rc6-00105-g279b1e0
> >
> > who automagic get updated when ever I run make install.
> >
> > The corresponding part of grub.conf is
> >
> > title Gentoo Linux (OpenRC)
> >        root (hd0,1)
> >        kernel /vmlinuz root=/dev/sda3 radeon.agpmode=-1
> > video=radeon:1440x900 zcache
> >
> > and
> >
> > title Gentoo Linux.old (OpenRC)
> >        root (hd0,1)
> >        kernel /vmlinuz.old root=/dev/sda3 radeon.agpmode=-1
> > video=radeon:1440x900 zcache
> >
> > That is all, no changing grub.conf and always the latest kernel.
>
> I've used the same method as you "forever" and it works great, and
> always easy fail-safe to boot previous kernel in case I got something
> wrong on the new one.
>

Hmm... my email server's seem to be getting flaky... I never received
Sebastian's...

Anyways, back to topic: I experiment a lot with the kernels, so I timestamp
them all, and my grub menu lists all kernels found in /boot, complete with
their respective timestamps. That way,if a .config change I did on K-1
(current is K-0, K-1 is the one before current) only now proved to be
flaky, I can 'roll back' to K-2 or earlier.

Rgds,

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Re: [gentoo-user] ext4/ext3 for /boot?

[Neil Bothwick]

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On Wed, 9 Nov 2011 09:44:00 +0700, Pandu Poluan wrote:

> Anyways, back to topic: I experiment a lot with the kernels, so I
> timestamp them all, and my grub menu lists all kernels found in /boot,
> complete with their respective timestamps.

The kernel build scripts can do this for you automatically, search for
LOCALVERSION. It's not a timestamp but an incrementing counter. If I need
to know the exact date and time the kernel was built, I can always us
ls -l :)


-- 
Neil Bothwick

Suborbital Ballistic-Propulsion Engineer
Not Exactly A Rocket Scientist

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Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

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On Nov 9, 2011 5:02 PM, "Neil Bothwick" <neil@digimed.co.uk> wrote:
>
> On Wed, 9 Nov 2011 09:44:00 +0700, Pandu Poluan wrote:
>
> > Anyways, back to topic: I experiment a lot with the kernels, so I
> > timestamp them all, and my grub menu lists all kernels found in /boot,
> > complete with their respective timestamps.
>
> The kernel build scripts can do this for you automatically, search for
> LOCALVERSION. It's not a timestamp but an incrementing counter. If I need
> to know the exact date and time the kernel was built, I can always us
> ls -l :)
>

I personally prefer timestamps, because my changelogs all have timestamps
in their name. The reason is that I may sometimes have to revisit (edit) a
changelog; the file's modification time gets changed, but the timestamp
stays :-)

Rgds,

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Re: [gentoo-user] ext4/ext3 for /boot?

[bill.longman]

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Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

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On Nov 9, 2011 11:02 AM, <bill.longman@gmail.com> wrote:
>
> I have a script that does the menuconfig + diff .config + make +
> install (including kernel copying to /boot, automagically mounting
> /boot if needed), so I can get away with noauto ;-)
> Oh, and it also auto-modifies grub.cfg for me :-D
>
>
> Oh, you use genkernel, too?
>
> :-}

LOL no...

I call it "pepo's kernel factory". pfk, for short :-}

Rgds,

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Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

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On Nov 9, 2011 11:16 AM, "Pandu Poluan" <pandu@poluan.info> wrote:
>
>
> On Nov 9, 2011 11:02 AM, <bill.longman@gmail.com> wrote:
> >
> > I have a script that does the menuconfig + diff .config + make +
> > install (including kernel copying to /boot, automagically mounting
> > /boot if needed), so I can get away with noauto ;-)
> > Oh, and it also auto-modifies grub.cfg for me :-D
> >
> >
> > Oh, you use genkernel, too?
> >
> > :-}
>
> LOL no...
>
> I call it "pepo's kernel factory". pfk, for short :-}
>

(and it's obvious that not yet having my first cup of coffee for the day
does wonders to my spelling ability)

Rgds,

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Re: [gentoo-user] ext4/ext3 for /boot?

[bill.longman]

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Re: [gentoo-user] ext4/ext3 for /boot?

[Pandu Poluan]

On Wed, Nov 9, 2011 at 12:22,  <bill.longman@gmail.com> wrote:
>> I call it "pepo's kernel factory". pfk, for short :-}
>>
> (and it's obvious that not yet having my first cup of coffee for the day
> does wonders to my spelling ability)
>
> But, for some reason, I like pfk much better than pkf. Maybe because it
> types a little faster! Or maybe your first coffee wasn't coffee and you
> called it pepo's fernel kactory....I'm not as think as you drunk I am.
>

Maybe because "pfk" sounds very much like "PFY" of "BOFH" fame?

:-P

Rgds,
-- 
FdS Pandu E Poluan
~ IT Optimizer ~

 • LOPSA Member #15248
 • Blog : http://pepoluan.tumblr.com
 • Linked-In : http://id.linkedin.com/in/pepoluan

Re: [gentoo-user] ext4/ext3 for /boot?

[J.Marcos Sitorus]

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On Tue, Nov 8, 2011 at 7:35 PM, Neil Bothwick <neil@digimed.co.uk> wrote:
>Leaving /boot unmounted invites the inevitable error of forgetting to
>mount it before installing a new kernel. I prefer to mount it ro, that
>way its contents are available, protected from accidental overwriting and
>it shouts at you if you forget to remount it before installing a kernel
>or updating GRUB.

Nice tips. It is very useful if you often compile kernel


-- 
Salam,

J.Marcos S.
Sent from X1™

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Re: [gentoo-user] ext4/ext3 for /boot?

[Stroller]

On 8 November 2011, at 08:37, Alan Mackenzie wrote:
> ...
>> The benefits of ext3/4 are irrelevant for /boot anyway - that
>> filesystem is write-seldom, read ever so slightly more often.
> 
> Really?  I put my PC into power saving mode before going to bed each
> evening.  The PC needs to read /boot to return to normal operation.

But in this case you're only reading from it. The writes are still very seldom, so journalling &c is unneeded. 

I've never used sleep / hibernate on Linux, but if it requires /boot then mount it read-only, as suggested by Neil Bothwick for other reasons.

Stroller.

Re: [gentoo-user] ext4/ext3 for /boot?

[Neil Bothwick]

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On Tue, 8 Nov 2011 15:52:54 +0000, Stroller wrote:

> I've never used sleep / hibernate on Linux, but if it requires /boot
> then mount it read-only, as suggested by Neil Bothwick for other
> reasons.

Sleep doesn't need access to /boot, the bootloader loads the kernel from
the boot partition in the usual way, but there is no need to mount the
filesystem.


-- 
Neil Bothwick

(A)bort (R)etry (S)ell it

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Re: [gentoo-user] ext4/ext3 for /boot?

[David Guillermo]

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Hi Jarry, ext2 abd don't auto mount boot in boot :)


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Re: [gentoo-user] ext4/ext3 for /boot?

[Alan McKinnon]

On Tue, 8 Nov 2011 08:37:24 +0000
Alan Mackenzie <acm@muc.de> wrote:

> On Mon, Nov 07, 2011 at 09:26:50PM +0200, Alan McKinnon wrote:
> 
> > ext2/3/4 are all backwards compatible. ext4 does have a certain
> > feature (I forget what) that once used breaks this compatibility
> > but you are highly, highly unlikely to ever do that on /boot.
> 
> > The benefits of ext3/4 are irrelevant for /boot anyway - that
> > filesystem is write-seldom, read ever so slightly more often.
> 
> Really?  I put my PC into power saving mode before going to bed each
> evening.  The PC needs to read /boot to return to normal operation.

So that part of the disk is read once a day. How many reads are made in
a day on the rest of the disk?

It still fully qualifies as "seldom". Let's put it in human terms - if
a single read to the disk were equivalent to one day on human terms,
you are looking at a read every 45 lifetimes.

-- 
Alan McKinnnon
alan.mckinnon@gmail.com

Re: [gentoo-user] ext4/ext3 for /boot?

[Alex Schuster]

Jarry writes:

> just out of curiosity: is it possible to use ext4/ext3
> filesystem even for separate /boot partition?

Yes. But a separate /boot partition is small, it is seldomly being
written to, it is often unmounted anyway, and a fsck is very fast on
such a small partition. So there is not much benefit of having a
journal. On the contrary, the journal takes some space that is wasted.
So I would just use ext2. But if you have the space, ext4 is fine.

	Wonko

Re: [gentoo-user] ext4/ext3 for /boot?

[pk]

On 2011-11-07 19:29, Jarry wrote:

> just out of curiosity: is it possible to use ext4/ext3
> filesystem even for separate /boot partition?

I've been using ext4 for quite a while as a /boot partition. One of the
"features" of ext4 is that you can use it without a journal (while still
using extents and other benefits[1]), which is what I'm doing (for /boot
- journal for the rest of the partitions)... but I wouldn't worry too
much about a partition that's usually measured in 100MBs; ext2 will be
fine too.

[1] http://kernelnewbies.org/Ext4

Best regards

Peter K