What's with the ReiserFS data safety thing?

published Oct 12, 2006, last modified Jun 26, 2013

I constantly hear people badmouthing ReiserFS (V3). For example, see the comments on the APC article. I don't really need to read an article to know that: even one of my college professors (who contributes to the Linux kernel) has told me so. I don't know if it's because people are misinformed... but I'll pitch in with my two cents:

Update: if you value your information, you may want to consider skimming over the tables and conclusions of this paper that discusses file system failure policy -- or (in short words) how different file systems cope with different types of failure. You might be surprised by its conclusions!

I don't understand why people keep assigning blame on ReiserFS when they lose data because of faulty hardware. Ironically, the complexity of on-disk structures in ReiserFS filesystems is greatly derived by the fact that ReiserFS takes pains to ensure data is written properly, while tuning for performance.

I'll tell a short story: I once had a 40 GB hard disk go bad on me, and it was ReiserFS-formatted, plus chock-full of my (then small) invaluable MP3 collection. How did that turn out? I only lost two files that used bad sectors. I didn't have to use the reiserfsck tool. How's that for resilience? Evidently, I still use Reiser (V3) to the day, in all of my disks.

How do I guard for data corruption? Backups, my friends. I have an LVM volume that combines two old disks, encrypts them with LUKS, and cron does a nightly backup to the LVM volume, through dirvish (yay! incremental backups with an option to access old files if I screwed up inadvertently and deleted important files, then let a few days go by). For extra safety, the LVM volume is unmounted when it's not in use, and their component disks are actually turned off by hdparm. Oh, and an UPS/surge protector combo protects my computer, just in case lighthing bolts (or, much more probably, morons from the electric company) hit my 4-story building.

I actually went out of my way to get all partitions formatted with ReiserFS, because my Fedora installer didn't offer it as an install-time option. I think I should also commend ReiserFS's blazing speed in a (majorly small-file based) regular Linux system like mine.

Bottom line: if you feel your data is at risk by combining ReiserFS and bad hardware, do us all a favor, be stupid and use FAT32 or something. Oh, you don't have a backup, right? Then don't whine about data loss, and get over it: you've already proven by your inaction that your data isn't important to you at all. I'll grant you this: my backup setup was quite hard to assemble, but I don't have enough money to go around shopping for RAID or external backup solutions; yet, backup solutions for Linux are (figuratively and literally) a dime a dozen nowadays, so my case is no excuse for you.

I'm willing to share my backup automation scripts with you. Just post a comment here and I'll contact you back soon. In any case, I sincerely hope the Reiser family comes out OK from the ordeal they're going through.