Measuring time servicing individual softirqs

Similar to what we did previously with hardirqs, we will now employ the softirqs[-bpfcc] tool. It displays the total time spent servicing softirqs (software interrupts). Again, you will require root access to run these [e]BPF tools.

First, let's place our system (native x86_64 running Ubuntu) under some stress (here, it's performing network downloads, network uploads, and disk activity). The following screenshot shows us running the softirqs-bpfcc tool, which provides information about the total time spent servicing softirqs every 1 second (first parameter) forever (no second parameter):

Figure 4.16 – softirqs-bpfcc displaying the time that was spent servicing softirqs every 1 second (under some I/O stress)

Notice how the tasklet softirq also comes into play.

Let's look at another example of using the same tool to generate a histogram of soft IRQ time distribution...