Warum ist Multithreading ein wichtiges Thema auch bei Computerspielen?
Moderne Betriebssysteme teilen die Last einer Multithreading-verwendenden Anwendung vollautomatisch auf alle vorhandenen Prozessorkerne auf – mit dem Höchsttakt eines einzelnen Kernes, so wird eine verbesserte Reaktivität des Betriebssystems gewährleistet als auch die Performance jeder einzelnen Anwendung erhöht.
Which is the best definition of multithreading?
Multithreading is the phenomenon of executing more than a thread in the system, where the execution of these threads can be of two different types, such as Concurrent and Parallel multithread executions. A Thread can be defined as a chunk or unit of a process that can be identified as either a user-level thread or a Kernel-level thread.
How are user level threads different from kernel level threads?
User-level threads [User-level threads are named to distinguish them from kernel-level threads, which are the concern of systems programmers, only. Because this book is for application programmers, kernel-level threads are not discussed.] are handled in user space and avoid kernel context switching penalties.
How is thread scheduling a problem in multithreading?
Thread scheduling is also a major problem in multithreading. The simplest type of multithreading occurs when one thread runs until it is blocked by an event that normally would create a long-latency stall. Such a stall might be a cache miss that has to access off-chip memory, which might take hundreds of CPU cycles for the data to return.
Why are user level threads inexpensive to create?
When an application binds threads to execution resources, the threads become kernel resources (see „System Scope (Bound Threads)“for more information). To summarize, user-level threads are: Inexpensive to create because they do not need to create their own address space.