Admin Table of Contents
What kind of process is switching?
Process switching refers to the process by which the router’s CPU or processor is directly involved in the forwarding decision. As a packet is process switched through the router, its CPU is responsible for choosing the appropriate process to handle the packet and schedule the running of the process.
What is the difference between process switching and fast switching?
Process switching is the oldest, slowest and most processor intensive. In fast switching, the first packet to a destination is process switched but subsequent packets are forwarded using the information stored in the fast cache. Finally, CEF pre-builds the cache before any packets need to be forwarded.
How do I enable a process switch?
To enable process switching on an interface, use the no ip route-cache command, which disables the route cache on an interface. A new route must be selected for every packet of a session. Now both lines are used to transmit that session’s data.
What is Cisco fast switching?
Fast switching allows higher throughput by switching a packet using a cache created by the initial packet sent to a particular destination. Destination addresses are stored in the high-speed cache to expedite forwarding. Routers offer better packet-transfer performance when fast switching is enabled.
Why is process switching?
To control the execution of processes, the kernel must be able to suspend the execution of the process running on the CPU and resume the execution of some other process previously suspended. This activity goes variously by the names process switch , task switch , or context switch .
What happens during a process switch?
In computing, a context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point. This allows multiple processes to share a single central processing unit (CPU), and is an essential feature of a multitasking operating system.
What is the difference between process switch and context switch?
Process context switching takes place when the operating system’s scheduler saves the current state of the running program(current process) (including the state of PCB) and switches to another process whereas Thread context switching takes place when the CPU saves the current state of the thread and switches to another …
What is context switching in OS?
What is IP route cache?
The route cache allows outgoing packets to be load-balanced on a per-destination basis. The ip route-cache command with no additional keywords enables fast switching. Our routers generally offer better packet transfer performance when fast switching is enabled, with one exception.
What is packet switching technique?
Packet Switching transmits data across digital networks by breaking it down into blocks or packets for more efficient transfer using various network devices. The network devices can then route the packets to the destination where the receiving device reassembles them for use. …
What is context switch overhead?
Context Switching Overhead. Context Switching Overhead. Each task switch takes a certain amount of time for the CPU to change the process environment. Too many task switches (i.e. quantum too small) means a greater proportion of CPU time is spent doing task switches instead of useful work.
What causes context switching?
The most common reasons for a context switch are: The time slice has elapsed. A thread with a higher priority has become ready to run. A running thread needs to wait.