Yes and no. The reason it isn't quite the same is that RAID storage has no ability to recovery corruption generated by the filesystem code itself or corruption caused by other parts of the kernel or by hardware snafus which occur prior to the data getting onto the platter. When you do logical replication, however, the possibility of this sort of corruption seeping into all the replicated copies is greatly reduced and the replicated copies can check against each other t...

This is the functional equivalent of a RAID1, and that is all HAMMER provides; the point of RAIDZ (and RAID3,4,5,6,etc) is that you don't need 2n bytes worth of disk for n bytes worth of usable storage, yet keeping some level of resilience. There is something to be said for this kind of scheme, namely not wasting as much disk space, but in the case of RAID1,0,10,01, moving that to a different layer (e.g. Vinum) is good enough. In a clustering environment, it's not likely that you'll want an...

I get a good 8 hours of sleep. As I get older I find myself unable to pull all-nighters any more without really screwing up the entire next day. -- ZFS serves a different purpose and I think it is cool, but as time has progressed I find myself liking ZFS's design methodology less and less, and I am very glad I decided against trying to port it. I do not think it is a good idea to put all one's marbles in a single copy of a filesystem, no matter how redun...

Ok, here's the final design document that I am now implementing. Again, I expect most or all of these features to be ready and the filesystem to be beta-quality by the December release. Hammer Filesystem (I) General Storage Abstraction HAMMER uses a basic 16K filesystem buffer for all I/O. Buffers are collected into clusters, cluster are collected into volumes, and a single HAMMER filesystem may span multiple volumes. HAMMER maintains a small hinted r...

*snip* Matt, Awesome! Tells me: "ZFS, bend over, grab your ankles and kiss your an(atomy) 'Goodbye'" From the amount of work that has HAD to go into this, it also tells me you are: A) probably single, or soon will be and B) don't sleep much anyway! ;-) Looking forward to a 'test drive'... Bill Hacker