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GPU621/False Sharing

3 bytes added, 17:02, 26 November 2021
Drawbacks
=== Drawbacks ===
While our idea works, there are several issues that prevent it from being an ideal solution.: 
'''- tons of wasted memory'''
For every 4 bytes for storing a thread's calculation, 60 bytes is empty padding. This empty space increases rapidly as the number of threads increases.
 
'''- the cache line only contains one piece of data with the rest being completely empty'''
This is what we wanted, but this is incredibly inefficient. The whole point of the cache is to improve performance by contain relevant data to minimize cache misses. In practice, a processor will likely be juggling other threads with their own data that may or may not be related to this program. By padding out the cache line, we are forcing cache misses to occur.
 
'''- must know cache size.'''
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