2008/10/22 Arend-Jan Wijtzes <ajwytzes at wise-guys.nl>: > On Wed, Oct 22, 2008 at 08:49:27AM +0530, Basavanagowda Kanur wrote: >> On Wed, Oct 22, 2008 at 3:49 AM, Mario Bonilla <hatrickmario at hotmail.com>wrote: >> >> > The architecture of GlusterFS configured as a RAID-1, using 2 nodes, the >> > writing is done in a node and is replicated in the other node, >> > question: the reading is done in parallel, since the two nodes where the >> > information is replicated? >> >> >> no.. reading is not done in parallel.. >> read is done from first available node. >> if read from first node fails, >> then read is done through next available node. > Is this behaviour required for correct operation? Does this mean that all > clients are always reading from the same availble first node? > Wouldn't the load be better distributed if you take a random or > 'round robin' node to read from (which would seem trivial to implement)? That is correct. Gowda gave you a simplified view of the operation. The AFR translator supports a 'read-subvolume' option, which lets you specify the node from where all the reads should be done. If you don't specify the option, reads will be balanced in a nearly round-robin fashion among all alive nodes. Vikas Gorur -- Engineer - Z Research http://gluster.org/
