Design of New Hash Mapping Functions

XY ‐Type GPU Cache: Exploiting Spatial Localities in both X and Y Directions to Avoid Conflict Miss

“…However, this method requires monitoring all the memory-resident variables, and also decreases the effective utilization ratio of cache memory. Fenglong Song et al proposed a hash function [5] : scatter the cache lines by doing XOR operation between some bits of the data address and a matrix Composed of 0 and 1. Chuanjun Zhang proposed a balanced cache [6] which used a programmable sub-array decoder to balance accesses to cache sets.…”

“…Finally, the resolution in the X direction can be any value, while the capacity of a GPU cache is a fixed value determined in the design phase. Doing XOR operation on some bits of data address cannot guarantee the same effective dispersion of cache lines in the Y direction as in the X direction [1,2,5] . Fig.1 shows the cache index distribution on the frame buffer achieved by the index mapping scheme proposed in Ref.…”

“…Fig.1 shows the cache index distribution on the frame buffer achieved by the index mapping scheme proposed in Ref. [5]. In Fig.1 a cache line is simplified to a grid and the number in a grid represents the cache line index.…”

“…The data in the drawn rectangle are mapped to the cache lines: No. [3][4][5][6][7] and No.27-31. Cache line conflict will occur once in each above cache line.…”

“…1. Cache index distribution on the frame buffer achieved by the index mapping scheme [5] III. XY -Type GPU Cache Index Mapping Scheme and Hardware Implementation…”