Going Full Send on my WFH A/V setup

I tried hard to make it work. But I could never get the results I wanted. The crisp video, clean audio, the BOKEH. Herein lies my adventures (full send, some might say) over the past ~2 months in getting a proper home office A/V setup. It’s not perfect yet, but I’m fairly happy with the improvement. I’ll close this write-up with some of my next steps / gaps.

Starting with some basic tenets:

Whatever I end up with has to augment all of my ingrained behaviors; I’m not going to relearn how to use a computer (change operating system) for the sake of this.
I’m stuck with the room I’ve got. The walls have odd angles which makes lighting difficult.
I don’t know anything about this, so there will be lots of trial, error, and Googling.

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Docker operations slowing down on AWS (this time it’s not DNS)

I’m CC’d on mails when things get slow, but never when things work as expected or are fast…oh well. Like an umpire in baseball, if we are doing our jobs, we are invisible.

Subject:  Docker operations slowing down

I reach for my trusty haiku for this type of thing:

Ah but in this scenario, it is something more…sinister (my word). What could be more sinister than DNS, you say? It’s the magical QoS system by which a cloud provider creatively rents you resources. The system that allows for any hand-wavy repackaging of compute or network or disk into a brand new tier of service…

Platinum. No, super Platinum. What’s higher than platinum? Who cares, we are printing money and customers love us because we have broken through their antiquated finance process. We will gladly overpay via OpEx just to avoid that circus.

But I digress…

In this scenario, I was working with one of our container teams folks who had a report of CI jobs failing and someone had debugged a bit and pinned the blame on docker. I watch the reproducer run. It is running

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Juggling backing disks for docker on RHEL7, using atomic storage migrate

Quick article on how to use the atomic storage commands to swap out an underlying 6852258 storage device used for docker’s graph storage.

I am currently using overlay2 for docker storage, and /var/lib/docker is currently on my root partition
I want to add a 2nd disk just for docker storage.
I want to keep my images, rather than have to download them again.

I have a few images in my system:

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nsinit: per-container resource monitoring of Docker containers on RHEL/Fedora

The use-case for per-application resource counters

Administrators of *NIX-based systems are quite accustomed to viewing resource counters strewn throughout the system, in places like /proc, /sys and more recently /cgroup or /sys/fs/cgroup. With the release of RHEL6 came widespread enterprise adoption of Control Groups (cgroups), which had been implemented steadily over a series of years, and vetted both there as well as in Fedora (RHEL’s upstream).

Implementing cgroups not only let sysadmins carve up a single OS into multiple logical partitions, it also bought them per-cgroup counters that the kernel maintains. That’s in addition to common use-cases such as quality of service guarantees or charge-back.

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Using SCHED_FIFO in Docker containers on RHEL

Well, I’ve been asked about this quite a few times now, so I figured a blog post was in order…

When I was trying to get cyclictest running in a container, I ran into a little snag. I couldn’t run realtime prio tasks inside a container by default. I checked all the normal ulimit stuff for RT, but no dice. But I did find a way (ugly).

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