For the majority of my life, I was not a social drinker. Not only did I abstain from alcohol, but also any sort of caffeine not found in a good hot chocolate. I made it through high school, college, and the first years of my professional life without a beer, latte, or late-night crunch energy drink.

Some of it was personal morals, but most of it was personal taste. I would sip friends’ drinks, make a face, and return to my water and cake. I was fine with this, because I was staying true to myself. And the people worth keeping in my life didn’t care. But I knew I was missing out.

About a month ago, I had the pleasure of taking a tutorial led by the fantastic Brendan Gregg on creating FlameGraphs using the Linux perf toolset. I recommend reading his many blog posts on the subject, but in short: while perf is an excellent resource for debugging kernel and user space processes, FlameGraphs make the data even easier to consume.

Now, if the process you’re trying to profile is Java, there are some extra hoops to jump through, which Brendan has also detailed online.

But if the Java process is in a container, it’s even more annoying. That’s where this post comes in.

On Monday evening I launched a Teespring campaign to raise money for Outreachy, a fantastic nonprofit that helps underrepresented people in tech find internships. The shirt in question reads “‘LADIES’ IS GENDER NEUTRAL” and is only offered in women’s sizes. However, I presented the women’s sizes as unisex and replied to requests for men’s sizing with phrases women have heard many times.

This rustled some jimmies.

Regardless, the campaign took off and, as of writing this post, we have raised over $2k for Outreachy. Many people jumped onboard, excited to turn the tables on the many uses of “guys” as a gender-neutral term of address.

However, “ladies” is not gender-neutral. Neither is “guys.”

That’s the point.

Back in January I decided to toy around with some internal tooling, so our support staff could directly page specific engineering teams. To do this, I dug into PagerDuty’s REST API with the aim of making a simple UI in front of it.

That’s when I noticed something strange.

After a few minutes of staring at the screen, cogs slowly turning, I had my weekend planned.

So, a server rebooted. Perhaps I’ve been lucky in the developers I work with, but whenever a host reboots, I always think hardware failure first. I treated this case no differently and jumped onto the host to run some quick diagnostics.

Since I deal in Dell equipment, my first stop is always check_openmanage. It gives a quick report on CPUs, DIMMs, chassis, power supplies, etc from the command line and takes about 30 seconds to run. It rarely fails me.

However, this time it did. Everything returned [OK]. No hardware failures.

I double-checked this claim on the iDRAC, just in case this was the one time in history a GUI was more correct than the modules running directly on the box. Nope, everything was green.

So I loaded up the kernel dump.