In update based protocols with a large number of processors, a lot of the bandwidth is occupied by the update operations since the same cache line might have to be updated on all the processors. The following 2 scenarios make the updates useless:
1) The updated value is never read again from the various processors whose cache lines were updated.
2) There are a lot of subsequent updates before the other processors read from the cache line.
The above scenarios adversely affect performance in update based protocols.
In update based protocols with a large number of processors, a lot of the bandwidth is occupied by the update operations since the same cache line might have to be updated on all the processors. The following 2 scenarios make the updates useless:
1) The updated value is never read again from the various processors whose cache lines were updated.
2) There are a lot of subsequent updates before the other processors read from the cache line.
The above scenarios adversely affect performance in update based protocols.