Use of IRQ

The following is the CPU state of the top of a single server:

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The Linux si can be seen in the/proc/interrupt:

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They have the following meanings:

IRQ number, each program corresponds to the number of SI times occurring on the CPU core, the programmable interrupt controller, the program name (also called the device)

The IRQ is all called the interrupt request, which means "interrupt requests", that is, the program requests the CPU to process its own requests. Each program (device) has its own corresponding IRQ number, the IRQ number in the/PROC/IRQ directory, the corresponding relationship between each number and the program name.

For servers with high concurrency scenarios, the CPU usage of the NIC is also quite high, so if it occupies a CPU core, it will not only affect the performance of the system, but also affect

in each computer system, it is an interrupt controller 8259 or 8259A chip (now the chip is mostly integrated into other chips) to control the system of each hardware interrupt control. There are currently 16 sets of IRQ, removing A set of IRQ used for bridging, in fact only 15 sets of IRQ for hardware calls.

This article is from the "Go Right on" blog, so be sure to keep this source http://caduke.blog.51cto.com/3365689/1600379

Use of IRQ