DPCs
DPCs, or Deferred Procedure Calls, are a kernel mechanism used by the Windows operating system to defer work that cannot be safely performed at an interrupt level. When a device interrupt occurs, the corresponding interrupt service routine (ISR) runs at a high interrupt request level (IRQL) and handles only time-critical tasks. The ISR often queues a DPC for later processing, allowing more extensive work to be completed outside the immediate interrupt context.
A DPC is represented by a small object containing a pointer to a routine (the DeferredRoutine) and
DPCs are typically per-processor to reduce cross-CPU locking and to improve latency. They are inserted with
In driver development, DPCs are a common mechanism to separate fast interrupt handling from slower processing,
Openly, DPC can refer to other concepts in different domains, but this article describes Deferred Procedure