Btrfs RAID 5/6 Code Found To Be Very Unsafe & Will Likely Require A Rewrite

[3DMan]

I have been using btrfs raid5 for over two years in production on my main server. I did not experieence any data loss and have been very satisfied with performance. As a result of the article and news I found here on Phoronix I decided to immediately take action to convert my raid 5 to raid 10 using this command:

btrfs balance start -dconvert=raid10 -mconvert=raid10 /media/raid

The conversion went well, no issues encountered.

[starshipeleven]

Why would be Alzheimer's a personal offence ?

It's a serious illness, and your whole post was just a big personal offence anyway.

So I tried to be useful.

Point out mistakes, you can call moron where moron is due, but snapping like that is a bit excessive imho.

It's a pitty that Douglas Adams died- he would be proud that he correctly predicted explosion of moron population.

Wrong, Internet just exposes more what is there (and has always been there) already. Morons have always been the majority of population.

[starshipeleven]

I forgot to add - and above all IRRESSISTIBLE URGE TO FORCE EVERYONE AROUND THEM into compliance witt their new idea.This is not about just BTRFS, it applies to everything - solar vs nuclear, batteries of the week, language of the future etc etc.

Well, this forum has a "ignore user" feature. It auto-hides all posts from specific users.
Many people find it nice.

I prefer to not close my eyes to the sea of moronic bs, and fight back for fun.

Also, I choose nuclear, LiFePo4 and English, thank you.

[starshipeleven]

Free space fragmentation means you will run out of free space eventually, even if there actually is enough free space. The counter argument to that is to script a solution using tools that are highly recommended by their own developers to never use.

I wasn't clear enough on this point, as hinted by someone else somewhere above, there is an "autodefrag" mount option that asks btrfs to deal with filesystem fragmentation automatically, so it's not something you need to worry about.

[jolebole]

My friend recently bought a Synology NAS and I was surprised that they were recommending he select btrfs during its setup. And he wanted to do RAID5, too.

I did upgrade from 2bay to 4bay Synology NAS couple months ago and during the setup I was offred to setup the Volume to BTRFS. I guess is back to Ext4 lol ..or FREENAS

[Brane215]

OTOH, that bcacheFS seems very interesting. It checks all boxes that interest me at the moment and offers answers to some problems that I thought until now affected just me.
Not to mention that I've thought this is caching system internal to kernel, now it seems they are about to expand this to whole new FS. Bravo.

I just have to try it with SSD+ HDD RAID combo.

[starshipeleven]

OTOH, that bcacheFS seems very interesting. It checks all boxes that interest me at the moment and offers answers to some problems that I thought until now affected just me.
Not to mention that I've thought this is caching system internal to kernel, now it seems they are about to expand this to whole new FS. Bravo.

I just have to try it with SSD+ HDD RAID combo.

Confusing bcache with bcachefs? It's a bit unclear what you mean here.

bcache is a cache filesystem and is currently in production for.... (suspance).... SSD cache for RAID arrays. I assume that this is the filesystem you want to try out cosnidering the "SSD+ HDD RAID combo".

bcachefs is based off the former, but is still under development and stuff may or may not work decently.
The guy behind it is on Patreon if you want to help others that are sponsoring him with monthly donations https://www.patreon.com/bcachefs

[Brane215]

I'm interested in both. I like bcache forusing as a cache for HDD and I like bcachefs as some effective FS that has data+metadata CRC. Snapshotting etc is nice to have, but by no mean essential for me.

WRT to donations, I'll check the product first. And then the developer. His wife's nationality, above all. I don't want to support someone that might end up murdering his russian wife...

[starshipeleven]

I'm interested in both. I like bcache forusing as a cache for HDD and I like bcachefs as some effective FS that has data+metadata CRC. Snapshotting etc is nice to have, but by no mean essential for me.

WRT to donations, I'll check the product first. And then the developer. His wife's nationality, above all. I don't want to support someone that might end up murdering his russian wife...

Nah, that guy seems sane, to the contrary of Reiser.
Can't comment on product quality, never used bcache myself.

While we are at it, did you check also SnapRaid? it can go up to 6 parity, and it runs checksums only on a schedule (which is better for most home NAS systems usually).

[nils_]

Nah, that guy seems sane, to the contrary of Reiser.

Why would you think Reiser is insane? Something to do with the filesystem or just the fact (beyond reasonable doubt...) he killed his wife?