Arch Linux

mbates

Member

Registered: 2014-07-09

Posts: 38

ext4-journal=ext2?

hi,

I am trying to install archlinux on a new ssd.  My plan is to use ext4 without journal for /.

But the problem is

 tune2fs -O "^has_journal" /dev/sda3

just turns sda3 from ext4 to ext2.

Is it normal? I mean without "journal", ext4 becomes ext2.  Or is there someting wrong?

thx

frostschutz

Member

Registered: 2013-11-15

Posts: 1,647

Re: ext4-journal=ext2?

Isn't journal the key feature of ext3/4 over ext2? Not that it really matters, those three filesystems are handled by the same driver nowadays, so you see things like TRIM support for ext2 even though the original ext2 driver does not have it.

Why don't you want the journal anyways? Without journal, fsck is slow. That is true for SSD as well.

If you're trying to minimize writes, stop that.

I use ext2 for /boot and maybe on small USB sticks; I would never use it for a full system or larger storage.

Last edited by frostschutz (2015-07-11 11:35:44)

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 9,003

Website

Re: ext4-journal=ext2?

If you're trying to minimize writes, stop that.

+1

New SSDs do not need such measures.
http://techreport.com/review/27909/the- … e-all-dead

---

Jin, Jîyan, Azadî

mbates

Member

Registered: 2014-07-09

Posts: 38

Re: ext4-journal=ext2?

thanks.

I take your advise.

And how about this

tmpfs    /var/log    tmpfs    defaults,nosuid,nodev,noatime,mode=0755,size=1G 0    0

PS: I hate journal, because it  increases fast, like 1 or 2 gigabyte in two months.

frostschutz

Member

Registered: 2013-11-15

Posts: 1,647

Re: ext4-journal=ext2?

tmpfs for logfiles? Well. If you never wish to look at your logfiles, that is probably fine ... ? logfiles have many uses though; if the system crashes, or you randomly notice one of your filesystems went into read-only mode - the cause may only to be found in the logfiles and you're losing them with every reboot. It's your decision, but not something I'd recommend in general...

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 9,003

Website

Re: ext4-journal=ext2?

I hate journal, because it  increases fast, like 1 or 2 gigabyte in two months.

https://wiki.archlinux.org/index.php/Sy … size_limit

---

Jin, Jîyan, Azadî

Scimmia

Fellow

Registered: 2012-09-01

Posts: 13,729

Re: ext4-journal=ext2?

Are you confusing filesystem journaling with the system journal?

mbates

Member

Registered: 2014-07-09

Posts: 38

Re: ext4-journal=ext2?

I hate journal, because it  increases fast, like 1 or 2 gigabyte in two months.

https://wiki.archlinux.org/index.php/Sy … size_limit

thx 4 the tips.

What I am more concerned about is the  total I/O, not the size on the disk.

mbates

Member

Registered: 2014-07-09

Posts: 38

Re: ext4-journal=ext2?

tmpfs for logfiles? Well. If you never wish to look at your logfiles, that is probably fine ... ? logfiles have many uses though; if the system crashes, or you randomly notice one of your filesystems went into read-only mode - the cause may only to be found in the logfiles and you're losing them with every reboot. It's your decision, but not something I'd recommend in general...

Thanks again.

How about only  /var/log/journal  instead of /var/log?  Is there any important info in this journal folder?

mbates

Member

Registered: 2014-07-09

Posts: 38

Re: ext4-journal=ext2?

Are you confusing filesystem journaling with the system journal?

Yes, I am confusing now.

In the /var/log/journal/, what info is stored there? ext4 or system?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 13,729

Re: ext4-journal=ext2?

That is the system journal, it has nothing at all do to with filesystem journaling.

mbates

Member

Registered: 2014-07-09

Posts: 38

Re: ext4-journal=ext2?

That is the system journal, it has nothing at all do to with filesystem journaling.

thx