Improve pseudoRandom performance with bitwise operation #51
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Currently, pseudoRandom calculation uses the mod operator, which turns into fmod in the end. On non-x86 platforms, there's no hardware accelerated fmod operation, which leads to a high CPU loading and bottleneck under the software fmod calculations. Since the divisor RANDOM_RANGE is a power of 2, it can be replaced by bitwise operation, which can improve the performance a lot on non-x86 platforms and make the workload and performance more aligned among all platforms. It can also slightly improve the performance on x86 platforms.
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Currently, pseudoRandom calculation uses the mod operator, which turns into fmod in the end. On non-x86 platforms, there's no hardware accelerated fmod operation, which leads to a high CPU loading and bottleneck under the software fmod calculations.
Since the divisor RANDOM_RANGE is a power of 2, it can be replaced by bitwise operation, which can improve the performance a lot on non-x86 platforms and make the workload and performance more aligned among all platforms. It can also slightly improve the performance on x86 platforms.