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This is incredibly inefficient. The whole point of the cache is to improve performance by contain relevant data We want to minimize cache misses. In practice, but by hogging valuable cache space this reduces the scheduler will be juggling many threads with their own data that may or may not be related to this program. By padding out effectiveness of the cache line. If we had a more complex program, we are hogging this valuable space and are forcing could have tons of other data the thread could have fit on the same cache misses to occurline.
→Presentation
'''- tons of wasted memory'''
For every 4 bytes for storing a thread's calculation, 60 bytes is empty paddingwhich grows for every new thread that is added. The more threads we haveEven though it is not a lot, the more wasted space there will beit is still very inefficient.
'''- the cache line only contains one piece of data with the rest being completely emptypadding'''
Identifying false sharing requires detailed code inspection as everything will appear to work normally on the surface. However, when left unchecked false sharing will be detrimental to the program's performance and scalability. This article discussed the relation between the cache and false sharing. In addition, using a simple example, we explained how you can use padding, synchronization, and thread local variables to reduce the frequency of false sharing.
== Presentation ==
PDF [[File:kchou_false_sharing.pdf]]
== References ==
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