Belle II grid computing : An overview of the distributed data management system.

The Belle II experiment at the SuperKEKB collider in Tsukuba, Japan, will start physics data taking in 2018 and will accumulate 50/ab of e$+$e- collision data, about 50 times larger than the data set of the Belle experiment. The computing requirements of Belle II are comparable to those of a Run I LHC experiment. Computing at this scale requires efficient use of the compute grids in North America, Asia and Europe and will take advantage of upgrades to the high-speed global network. We present the architecture of data flow and data handling as a part of the Belle II computing infrastructure.