The following command will print a stack trace whenever pcc_send_data is called.
sudo bpftrace -e 'f:pcc_send_data{print(kstack())}'Using bpftrace for PCC traffic
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Tools First
I have wasted a lot of time as a developer waiting for long running processes to complete. Whether it is a Linux Kernel compile, and Ansible Playbook tearing down and recreating a system on a remote server, or a gitlab pipeline building and testing code, the common problem is that my head is in the problem being addressed there, but I cannot do anything to verify hypotheses until the process completes. I often get distracted while waiting, and find that what could have been a 5 minute turn around has become a 2 hour turn around.
Continue readingFind files to download from Apache default pages
Apache provides a pretty standard screen to display directoyr contents if you do not provide any mods. We post artifacts up to a local server that I later need to download. Here are my hacky notes using command line utilities. I probably will convert this to python next.
Continue readingChord Analysis of All the Things You Are
Eventually I want to be able to smoothly recall the chords at speed. However, when memorizing them, it helps to have a series of mnemonics, and to chunk them together. Just as you practice a song slow before you play it fast, you memorize the chords slow.
Here is my analysis of “All the Things You Are.”
Continue readingMemorizing Chord Changes
I have been working on memorizing chords for a bunch of Standards and originals. It helps tremendously. A couple things that have worked for me:
Continue readingQuery FreeIPA by manager
A recent question lead me down a rabbit hole: how can we list the people that report up to George Slate? While we should be able to query this from LDAP, it seems to be shut off. However, using FreeIPA’s HTTP API, we can, if you know what you are doing. I do…
I call it my ctaginator
The Linux Kernel source is too big to generate all tags for all files. I want only a subset of C files and the corresponding headers. Here is my first take at it. yes it is in python. The program is designed to be run from the root of the Linux Kernel tree.
Continue readingTavolo
When the noise of the DotCom boom became too loud for me to ignore, I finally left my role enabling mainframes and joined a consultancy focusing on Electronic Commerce with a skillset based on Java. I was pretty well prepared for this, as the Object Oriented approach I had learned in the Visual C++ world translated over fairly cleanly, and I had taken a Java transition course at UC Berkely extenstion. Thus, I moved two streets up, two streets over, to the overheated, noisy, open bay office if Fort Point Partners.
Continue readingMapping a PCIe Device to its module on Linux
The Kernel docs are a little old. They point to the Device Drivers book, which was great, but quite outdated; it was written around version 2.6 and the Kernel is up to 6.15. Here are my notes that go from those docs to where things are today.
Continue readingvim windows
I tend to want to work with three windows side by side. Two have the code I am working with, often production code on the left, test code on the right. The third window is the output from running commands to test the code.
I recently have decide to go all-in on vim, and it is progressing nicely. Thank you the Jake Worth for inspiring this. In Vim, the meta key for for doing windows operations is Ctrl-W. Here are a few commands I have gathered up from the internet. I will collect up the links where I get them at the bottom