1 Introduction
2 Value iteration for a one product model
2.1 Decision model for one product
2.2 Value iteration to reach the optimal policy
2.3 Illustration for one product case
3 Handling two products due to substitution interaction
3.1 Value iteration for two products simultaneously
3.2 Two product instances
3.3 Complexity of the algorithm
Instance | ||||||||
---|---|---|---|---|---|---|---|---|
Nr products | 1 | 1 | 1 | 2 | 2 | 2 | 2 | 2 |
Shelf life M | 2 | 3 | 4 | 2 | 2 | 3 | 3 | 3 |
\(\overline{Q}_a\)
| 10 | 15 | 20 | 10 | 14 | 6 | 6 | 15 |
\(\overline{Q}_b\)
| 10 | 10 | 3 | 6 | 15 | |||
\(\mu _a\)
| 5 | 5 | 5 | 5 | 7 | 2 | 2 | 5 |
\(\mu _b\)
| 5 | 5 | 1 | 2 | 5 | |||
N
| 121 | 4096 | 194,481 | 14,461 | 27,225 | 21,952 | 117,649 |
\(16.8\times 10^6\)
|
Comp time | .03 s | 2.1 s | 9 min | 2 min | 6 min | 6 min | 99 min | xxx |
4 Parallelization of value iteration
5 Evaluation results
NVIDIA K80 | |
---|---|
Peak performance (double prec.) (TFlops) | 2.91 |
Peak performance (simple prec.) (TFlops) | 8.74 |
Device memory (GB) | 24 |
Boost clock rate (MHz) | 875 |
Memory bandwidth (GB/s) | 480 |
Multiprocessors | 13 |
CUDA cores | 4992 |
Compute capability | 3.7 |
P1 | P2 | P3 | P4 | |
---|---|---|---|---|
\(\mu _a\)
| 5 | 5 | 6 | 7 |
\(\mu _b\)
| 5 | 6 | 6 | 7 |
\(\overline{Q}_a\)
| 11 | 11 | 13 | 14 |
\(\overline{Q}_b\)
| 11 | 13 | 13 | 14 |
N
| 14,461 | 20,449 | 28,561 | 38,416 |
P1 | P2 | P3 | P4 | |
---|---|---|---|---|
Seq. code | ||||
Total runtime of Algorithm 3 | 357.89 | 698.20 | 1358.04 | 4241.66 |
Substitution (lines 14–19) | 351.31 | 688.71 | 1344.82 | 4217.15 |
GPU code | ||||
Total runtime | 91.29 | 136.84 | 214.71 | 361.49 |
Communication host to device | 0.00 | 0.00 | 0.01 | 0.01 |
Communication device to host | 21.55 | 23.35 | 43.63 | 56.69 |
GPUSubstitution | 39.94 | 67.29 | 111.99 | 215.54 |
Total Communic. GPU/CPU | 21.56 | 23.35 | 43.64 | 56.70 |
% Communications | 23.62 | 17.06 | 20.32 | 15.69 |
% GPUSubstitution | 43.75 | 49.18 | 52.16 | 59.62 |
% Other parts of VI | 32.63 | 33.76 | 27.52 | 24.69 |