On Fri, Sep 14, 2007 at 03:07:46PM -0400, Jeff Garzik wrote: > My thoughts. But first a disclaimer: Perhaps you will recall me as one > of the people who really reads all your patches, and examines your code and > proposals closely. So, with that in mind... > > I question the value of distributed block services (DBS), whether its your > version or the others out there. DBS are not very useful, because it still > relies on a useful filesystem sitting on top of the DBS. It devolves into > one of two cases: (1) multi-path much like today's SCSI, with distributed > filesystem arbitrarion to ensure coherency, or (2) the filesystem running > on top of the DBS is on a single host, and thus, a single point of failure > (SPOF). > > It is quite logical to extend the concepts of RAID across the network, but > ultimately you are still bound by the inflexibility and simplicity of the > block device. > > In contrast, a distributed filesystem offers far more scalability, > eliminates single points of failure, and offers more room for optimization > and redundancy across the cluster. > > A distributed filesystem is also much more complex, which is why > distributed block devices are so appealing :) > > With a redundant, distributed filesystem, you simply do not need any > complexity at all at the block device level. You don't even need RAID. > > It is my hope that you will put your skills towards a distributed > filesystem :) Of the current solutions, GFS (currently in kernel) scales > poorly, and NFS v4.1 is amazingly bloated and overly complex. > > I've been waiting for years for a smart person to come along and write a > POSIX-only distributed filesystem. What exactly do you mean by "POSIX-only"? --b. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
