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→Design questions: no. 1
==Design questions==
;Why is it fortunate that we did not ask you to implement priority donation for semaphores?
:Be damned Currently, each time a thread acquires a lock or calls {{c|join()}}, we know who is currently holding the resource. This allows us to donate priority to this single resource if I knowa higher-priority thread begins waiting on it. With semaphores, this is not possible for initial values greater than 1, because the last thread to successfully "acquire" the semaphore will not necessarily be the one with the lowest priority. The implementation would need to change to keep track of all threads that are actually using the semaphore currently and thus be able to determine which of those has the lowest priority and needs to "receive" a donation. Anyone?
;A student proposes to solve the boats problem by use of a counter, AdultsOnOahu. Since this number isn't known initially, it will be started at zero, and incremented by each adult thread before they do anything else. Is this solution likely to work? Why or why not?
:No, because there is no way of enforcing the fact that everyone will increment it before they do anything else.