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For example, the following case may cause bad performance:
| file space: | 2-D: the first dimension 1, the second dimension FSIZE |
| memory space: | 1-D: The fist dimension DMAX |
If you change it as follows:
| file space: | 2-D: the first dimension 1, the second dimension FSIZE |
| memory space: | 2-D: the first dimension 1, the second dimension DMAX |
Then, the performance may be much improved.