On Tue, 13 Nov 2007, Bryan Henderson wrote: > >Ceph is a distributed network file system ... > > What's distributed about it? As described, it sounds highly centralized. > Do you mean it is distributed across the nodes of the central server > clusters? Or just that it's a shared filesystem (multiple clients can use > it at the same time)? Both, actually, although there isn't necessarily a strong distinction between the 'central server cluster' and client nodes. For example, storage nodes can double as client nodes (as in a cluster doing distributed computation or some such thing). The system is distributed in the sense that there is no central server limiting scalability. Data storage is distributed across a large cluster of storage nodes (bricks or OSDs), and the metadata (namespace) is managed by a smaller cluster of metadata servers, allowing shared access to the filesystem by many many clients. Aggregate I/O throughput and capacity can be scaled more or less independently from metadata throughput (namespace manipulation) by adjusting the number of nodes devoted to each. sage - 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
