In recent years, concerns have arisen because of long latencies associated with some kernel run-times, sometimes on the order of 100ms or more in systems with monolithic kernels. These latencies often produce noticeable slowness in desktop systems, and can prevent operating systems from performing time-sensitive operations such as audio recording and some communications.
Modern operating systems extend the concepts of application preemption to device drivers and kernel code, so that the operating system has preemptive control over internal run-times as well. Under Windows Vista, the introduction of the Windows Display Driver Model (WDDM) accomplishes this for display drivers, and in Linux, the preemptable kernel model introduced in version 2.6 allows all device drivers and some other parts of kernel code to take advantage of preemptive multi-tasking.
Under Windows prior to Windows Vista and Linux prior to version 2.6 all driver execution was co-operative, meaning that if a driver entered an infinite loop it would freeze the system.
Modern operating systems extend the concepts of application preemption to device drivers and kernel code, so that the operating system has preemptive control over internal run-times as well. Under Windows Vista, the introduction of the Windows Display Driver Model (WDDM) accomplishes this for display drivers, and in Linux, the preemptable kernel model introduced in version 2.6 allows all device drivers and some other parts of kernel code to take advantage of preemptive multi-tasking.
Under Windows prior to Windows Vista and Linux prior to version 2.6 all driver execution was co-operative, meaning that if a driver entered an infinite loop it would freeze the system.
No comments:
Post a Comment