Jeff Garzik wrote: > Evgeniy Polyakov wrote: > > Hi. > > > > I'm pleased to announce fourth release of the distributed storage > > subsystem, which allows to form a storage on top of remote and local > > nodes, which in turn can be exported to another storage as a node to > > form tree-like storages. > > > > This release includes new configuration interface (kernel connector over > > netlink socket) and number of fixes of various bugs found during move > > to it (in error path). > > > > Further TODO list includes: > > * implement optional saving of mirroring/linear information on the > > remote nodes (simple) > > * new redundancy algorithm (complex) > > * some thoughts about distributed filesystem tightly connected to DST > > (far-far planes so far) > > > > Homepage: > > http://tservice.net.ru/~s0mbre/old/?section=projects&item=dst > > > > Signed-off-by: Evgeniy Polyakov <johnpol@xxxxxxxxxxx> > > 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. This http://lkml.org/lkml/2007/8/12/159 may provide a fast-path to reaching that goal. Thanks! -- Al - 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
