▶️ Intro On the previous post we started our journey with a very simple scenario, and we used a nice feature of the Go programming language to get a measure of how much % of the target program our test is exercising. This time I am going to experiment a Proof of Concept about how we can obtain a test code coverage metric estimation for a normal binary program, without any recompilation. ...
💭 What ? Imagine a web server that only starts when someone actually tries to access it. Or a database that spins up only when a query comes in: this is the magic of socket activation. The concept is not new, as old-school sysadmins may are used to see something like inetd or xinetd for on-demand service activation in the past. As some cool projects like cockpit have already started using this little-known feature, in this blog post we’ll see the basics and try to get familiarity with the tooling. ...
👻 Intro While our previous post focused on the core components of LTP tests, today in this part boo two we’re taking a spooky deep dive into the options available in struct tst_test 🦇. The Linux Test Project (LTP) began as a collaborative effort between SGI, OSDL, and Bull. Today, it lives with the joint contributions of industry leaders including IBM, Cisco, Fujitsu, SUSE, Red Hat, Oracle, and others. Its mission remains clear: providing the open source community with comprehensive tests that verify Linux’s reliability, robustness, and stability. 🕸️ ...
👣 Intro Tracing tools are pretty popular in the Unix/Linux ecosystem; for example in the userspace we have ltrace to trace library calls of the programs and strace to dive in deeper and inspect syscall usage. One of the many features that Linux kernel offers since 2008 (then evolved) is ftrace that allows many different kind of tracing at runtime. While not as flexible as eBPF technology, it can be helpful in some occasion and doesn’t require a full fledged programming language. ...