Here's a step-by-step guide to visualize Linux system calls in real-time on Ubuntu using theperf tool:

Prerequisites

• Make sure you have thelinux-tools-common andlinux-tools-generic packages installed. You can install them using:

sudoaptinstalllinux-tools-common linux-tools-generic

Visualizing System Calls in Real-Time

1. Open a terminal on your Ubuntu system.

2. Run the following command to start theperf trace and visualize system calls in real-time:
   

sudoperf trace--event'sys_enter*,sys_exit*'--event'sched:sched_switch'--event'sched:sched_wakeup'--event'sched:sched_process_exit'--event'sched:sched_process_free'--event'sched:sched_process_wait'--event'sched:sched_stat_sleep'--event'sched:sched_stat_wait'--event'sched:sched_stat_yield'--event'sched:sched_stat_runtime'--event'sched:sched_process_hang'--event'sched:sched_process_exec'--event'sched:sched_migrate_task'--event'sched:sched_process_fork'--event'sched:sched_process_exit'--event'sched:sched_process_free'--event'sched:sched_process_wait'--event'sched:sched_stat_sleep'--event'sched:sched_stat_wait'--event'sched:sched_stat_yield'--event'sched:sched_stat_runtime'--event'sched:sched_process_hang'--event'sched:sched_process_exec'--event'sched:sched_migrate_task'--event'sched:sched_process_fork'

This command enables tracing for various system call events and scheduler events. It provides a comprehensive view of the system's behavior.

1. The trace will start immediately, and you'll see system call events scrolling in the terminal.

2. To stop the trace, pressCtrl+C.

3. After stopping the trace,perf will generate a report file namedperf.data in the current directory.

4. To visualize the trace, run the following command:
   

sudoperf script | ./path/to/FlameGraph/stackcollapse-perf.pl | ./path/to/FlameGraph/flamegraph.pl> perf_viz.svg

Replace./path/to/FlameGraph/stackcollapse-perf.pl and./path/to/FlameGraph/flamegraph.pl with the actual paths to thestackcollapse-perf.pl andflamegraph.pl scripts from the FlameGraph repository.

1. This command generates an SVG file namedperf_viz.svg that visualizes the system call trace as a flame graph.

2. Open the generatedperf_viz.svg file in a web browser to view the flame graph.

The flame graph provides a visual representation of the system calls, their duration, and the call stack. The width of each bar represents the time spent in each function or system call, making it easier to identify performance bottlenecks and hotspots.

By following these steps, you can effectively visualize Linux system calls in real-time usingperf and the FlameGraph tool on your Ubuntu system. This technique helps in understanding system behavior, identifying performance issues, and optimizing applications.

Citations:
[1]https://xitoring.com/kb/strace-monitor-linux-system-calls/
[2]https://opensource.com/article/19/10/strace
[3]https://manpages.ubuntu.com/manpages/trusty/man1/strace.1.html
[4]https://dev.to/narasimha1997/lets-build-a-simple-system-calls-monitoring-dashboard-using-bpftrace-and-streamlit-2m1n
[5]https://www.pingcap.com/blog/how-to-trace-linux-system-calls-in-production-with-minimal-impact-on-performance/
[6]https://www.howtogeek.com/732736/how-to-use-strace-to-monitor-linux-system-calls/
[7]https://en.wikipedia.org/wiki/Kernel_%28operating_system%29
[8]https://sysprog21.github.io/lkmpg/