What was the story with tux3? It looks like it "read and wrote it's first file" in August 2008, and then had it's last update a few months later in Dec 2008. If if never got out of heavy development phase, being in the kernel wasn't the right place for it.
ReiserFS 4, it's been a very long time since I thought about it, but ISTR there were technical issues the needed to be addressed to bring it in mainline, and personality issues didn't help any, but that's a fading memory. Which is unfortunate, because ReiserFS had some great features.
On the other hand, btrfs made it into the kernel fairly easily, as a counterpoint. It's a unusual situation because it's been fairly broken and in heavy development for much of it's life in kernel, but early in-kernel versions were actually working fairly good (in my experience, I ran some fairly early versions in my laptop for a year or two with good luck, then an OS update brought in a new version and I had terrible corruption issues.
ReiserFS 4, it's been a very long time since I thought about it, but ISTR there were technical issues the needed to be addressed to bring it in mainline, and personality issues didn't help any, but that's a fading memory. Which is unfortunate, because ReiserFS had some great features.
On the other hand, btrfs made it into the kernel fairly easily, as a counterpoint. It's a unusual situation because it's been fairly broken and in heavy development for much of it's life in kernel, but early in-kernel versions were actually working fairly good (in my experience, I ran some fairly early versions in my laptop for a year or two with good luck, then an OS update brought in a new version and I had terrible corruption issues.