Difficulties
Automatic parallelization by compilers or tools is very difficult due to the following reasons:
- dependence analysis is hard for code using indirect addressing, pointers, recursion, and indirect function calls;
- loops have an unknown number of iterations;
- accesses to global resources are difficult to coordinate in terms of memory allocation, I/O, and shared variables.
Read more about this topic: Automatic Parallelization
Famous quotes containing the word difficulties:
“Have you noticed when reading War and Peace the difficulties Tolstoy experienced in forcing morally wounded Bolkonsky to come into geographical and chronological contact with Natasha? It is very painful to watch the way the poor fellow is dragged and pushed and shoved in order to achieve this happy reunion.”
—Vladimir Nabokov (18991977)
“Our achievements speak for themselves. What we have to keep track of are our failures, discouragements, and doubts. We tend to forget the past difficulties, the many false starts, and the painful groping. We see our past achievements as the end result of a clean forward thrust, and our present difficulties as signs of decline and decay.”
—Eric Hoffer (19021983)
“Let us consider that we are all partially insane. It will explain us to each other; it will unriddle many riddles; it will make clear and simple many things which are involved in haunting and harassing difficulties and obscurities now.”
—Mark Twain [Samuel Langhorne Clemens] (18351910)