What does it do?
Phoronix: Reiser4 Benchmarked On Linux 3.5
While the Reiser4 file-system has been in-development for the better part of the past decade, it still hasn't been merged into the mainline Linux kernel. Reiser4 is still out-of-tree, doesn't see much new development activity by its limited developers, and the file-system remains tarnished due to its founder, Hans Reiser, being a convicted murderer. However, Edward Shishkin the former Namesys employee, does continue to drive its development forward. Reiser4 was recently updated to work with the more modern Linux 3.5 kernel.
What does it do?
Is Reiser4 the "Brain fuck scheduler" of file systems ?
It has merits, and can be developed further to beat a lot of mainline FS's. But it wont be _ever_ introduced in the mainline kernel. For reasons that some critics say are biased against the _developer_ , rather than the technical merit of the code itself.
'whooped' in a 'majority'? Really? Well technically - because of threaded io tester.... if you take that one out everything changes. Or you could have written 'btrfs is whooped' ... well... whatever.
Btw, why did you miss to mention THE r4 feature? atomicy?
Rename data loss can happen with every FS - except reiser4.
Or wandering journal and dancing trees which are a nice way to spread the write load over the disk?
They never let it in the kernel. I personally believe that some ext people were even scared of ReiserFS's efficiency and didn't want it in the kernel. Not monocausal but this was also a reason.
Now, for being developed by so few (one?) persons, and being out of tree it still makes a good run. It's sad that it never really had the chance to go mainline. Ext was never _that_ great and btrfs is still fiddling with some issues and still not announced as ready for productive systems (but I'm glad Chris Mason is not at Oracle anymore).
But so there are some things, people, good ideas, sometimes ahead of their time. Masses laught at them, but much later everybody uses the same principle and agrees that this is now common standard.
Stop TCPA, stupid software patents and corrupt politicians!
Sorry to say it, but what's all the excitement about BTRFS when it sucks so much compared to EXT4. Why would any desktop Linux user in their right mind chose BTRFS???
ssds are gonna become the standard in five years anyway.