Performance
On a multi-core processor, native thread implementations can automatically assign work to multiple processors, whereas green thread implementations normally cannot. Green threads can be started much faster on some VMs. On uniprocessor computers, however, the most efficient model has not yet been clearly determined. Benchmarks on computers running the (ancient) Linux kernel version 2.2 have shown that:
- Green threads significantly outperform Linux native threads on thread activation and synchronization.
- Linux native threads have slightly better performance on I/O and context switching operations.
When a green thread executes a blocking system call, not only is that thread blocked, but all of the threads within the process are blocked. To avoid that problem, green threads must use asynchronous I/O operations, although the increased complexity can be hidden by implementing separate native I/O processes which cooperate with green threads.
Read more about this topic: Green Threads
Famous quotes containing the word performance:
“The value of old age depends upon the person who reaches it. To some men of early performance it is useless. To others, who are late to develop, it just enables them to finish the job.”
—Thomas Hardy (1840–1928)
“Having an identity at work separate from an identity at home means that the work role can help absorb some of the emotional shock of domestic distress. Even a mediocre performance at the office can help a person repair self-esteem damaged in domestic battles.”
—Faye J. Crosby (20th century)
“The child to be concerned about is the one who is actively unhappy, [in school].... In the long run, a child’s emotional development has a far greater impact on his life than his school performance or the curriculum’s richness, so it is wise to do everything possible to change a situation in which a child is suffering excessively.”
—Dorothy H. Cohen (20th century)