A single contiguous region is represented by a single structure. The region can be specified as SIZE bytes at location OFFSET as in figure A:
PTYPE: offset = OFFSET num_ereqs = SIZE stride = 1 num_blocks = 1 ub = SIZE lb = 0 aggregate_size = SIZE depth = 1 num_contig_chunks = 1 etype = PVFS_Request_byte stype = NULL
Or can be specified as an array of COUNT integers as in figure B:
PTYPE: offset = OFFSET num_ereqs = COUNT stride = 1 num_blocks = 1 ub = COUNT * 4 lb = 0 aggregate_size = COUNT * 4 depth = 1 num_contig_chunks = 1 etype = PVFS_Request_int stype = NULL PVFS_Request_int: offset = 0 num_ereqs = 4 stride = 1 num_blocks = 1 ub = 4 lb = 0 aggregate_size = 4 depth = 0 num_contig_chunks = 1 etype = NULL stype = NULL
Note that default PVFS_Request exist for standard data types including: PVFS_Request_byte, PVFS_Request_char, PVFS_Request_short, PVFS_Request_int, PVFS_Request_long, PVFS_Request_float, PVFS_Request_double. Each of these standard types is defined with an etype of NULL which indicates that the region is contiguous regardless of the other parameters.