# Some questions about UFS-J



## freethread (Aug 11, 2011)

I read some documents about UFS-J and the man pages too, so I guess I'm able to install a new system with UFS-J filesys. My questions are related to UFS-J requirements and performances and if it is enabled on the next release on FreeBSD (9.0).

My home server is an old machine, PII 466MHz 512MB RAM, in the past I ran in trouble with FreeBSD 8.0/8.1 and HDD (about 30-40 power failures per year, one of them was fatal), anyway, I should use an UPS. No UPS. The problem is not my personal data, it's the system configuration instead. In the past I spent a lot of time reconfiguring system, ports and services, now I have a virtualbox twin on another machine configured in the same way of the server (but it's not really the same) and an USB mem stick always plugged in with 6h buckup of all system/ports/personal configuration files and some scripts to configure a new installation.

Now, is appropriate to install UFS-J on a machine like the above? the services I run are httpd, mysql, qmail, and a not-so-often-used desktop (X server + XFCE + some WMs) primarily in remote but 99% I use remote console only. The term 'appropriate' refers to RAM and CPU.

The close to coming FreeBSD 9.0 will support (at installation time) UFS-J by default?

Thanks in advance for your replies


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## rusty (Aug 11, 2011)

Yes it will support SU+J at install. Currently the installer allows for options to be toggled when creating the filesystems, otherwise it's a case doing the following on an unmounted filesystem 
`# tunefs disable -j /dev/adaXsX`

Personally I'd play around with FreeBSD 9.0 and find the aceptable level of where journals are a benefit, a 1GB partition doesn't need a journal, however having a journal on a 80GB, 500GB or multi TB partition(s) is superb.

I had some dodgy memory that would randomly hard-lock this machine, after one hard-lock/reboot I found that Opera (which had been open at the time) had lost it's bookmarks, but that is the _only_ case of data loss I've had in a few months, and this machine had far too many random power cycles due to hard-locks.


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## freethread (Aug 12, 2011)

> Yes it will support SU+J at install. Currently the installer allows for options to be toggled when creating the filesystems



Ok, then it's better to install a fresh 9.0 with journaling on another HD instead of try to install journaling in the current system and then upgrade to 9.0.



> I had some dodgy memory that would randomly hard-lock this machine, after one hard-lock/reboot I found that Opera (which had been open at the time) had lost it's bookmarks, but that is the _only_ case of data loss I've had in a few months, and this machine had far too many random power cycles due to hard-locks.



I have some scripts that runs regularly and touch system files restart services, plus port updating every 1 or 2 weeks (max 2 days for compiling them, normally few hours). I reinstalled FreeBSD 8.1 in october 2010 and upgraded to 8.2 in march, suffered one black-out one month ago and not completed the last step of freebsd-update (from 8.1 to 8.2). Anyway, it runs like a swiss clock.

Thanks for info.


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## freethread (Aug 15, 2011)

Installed in a virtualbox the 9.0-BETA1 and seam all it works (but some net trouble during installation and Xorg, not real troubles, I guess this is a virtualbox + machine issue). SU+J (journaling) was easy to create.

Last question. Is still needed to start in single user mode and run fsck after a not proper shutdown?

P.S. Many thanks for SC_PIXEL_MODE (it postone the kernel rebuild) and MANWIDTH env var.


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## gkontos (Aug 16, 2011)

freethread said:
			
		

> Last question. Is still needed to start in single user mode and run fsck after a not proper shutdown?


The only time you need to start in single user mode and fsck after an improper shutdown is only when your system refuses to boot. So, no you don't need to do that either way.
Since you installed beta1 try to perform some abrupt reboots under heave disk I/O and you will see the difference when your system comes up.


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## rusty (Aug 16, 2011)

You might like to listen to this podcast, there's an interesting explanation of how it all works. http://bsdtalk.blogspot.com/2010/02/bsdtalk186-jeff-roberson.html

Or if you want to know more about SU+J in general http://jeffr-tech.livejournal.com/


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