However, consuming four IRQ lines for a single device quickly leads to IRQ line exhaustion. For example, in the previous example of the 7-in-1 media card reader, a much better solution is for each device to have its own interrupt and for one driver to manage the different interrupts knowing which device they came from. They are typically undesirable and a side effect of the limited number of physical interrupt lines on a computer. Shared interrupts are often the cause of high interrupt latency and can also cause stability issues. or another attempt to improve latenciesįrom 'Windows Internals' by Mark Russinovich, David A.