2.2. Software interrupt requests

Software interrupt requests (SoftIRQs) clear the receive ring buffers of network adapters. The kernel schedules SoftIRQ routines to run at a time when other tasks will not be interrupted. On RHEL, processes named ksoftirqd/cpu-number run these routines and call driver-specific code functions.

To monitor the SoftIRQ counters for each CPU core, enter:

# watch -n1 'grep -E "CPU|NET_RX|NET_TX" /proc/softirqs'
                    CPU0       CPU1	  CPU2       CPU3	CPU4	   CPU5       CPU6	 CPU7
      NET_TX:	   49672      52610	 28175      97288      12633	  19843      18746     220689
      NET_RX:         96       1615        789         46         31	   1735       1315     470798

The command dynamically updates the output. Press Ctrl+C to interrupt the output.