Posted on 2024-01-05

Hello,

Welcome to the 65th issue of TMPDIR, a weekly newsletter 📰 covering Embedded Linux, IoT systems, and technology in general. Please pass this on to anyone else you think might be interested. Suggestions and feedback are welcome at ✉️ info@tmpdir.org.

Thanks for reading!

Khem and Cliff

Quote for the week

Happiness is when what you think, what you say, and what you do are in harmony. -- Mahatma Gandhi

Best Wishes in the New Year

path woods

May your path be full of joy, peace, and fulfillment.

Thank you for a great 2023.

Looking forward to building in 2024!

Yoe 2023.12 release 🚀

Last release of 2023 is available. As is usual with rolling release, useful features and fixes keep rolling in.

Clang compiler was updated to 17.0.6 which is a bugfix release in 17.x series. LLD linker was disabled for x32 ABI, it does not have support to be enabled as system linker.
Odroid-C4 build is cleaned up and mesa-gl mali-g31 drivers can happily live together. yoe-kiosk-image is building and booting.
GDB 14.1 bring major debugger release into distro
Rust upgraded to 1.71.1 and go compiler to 1.20.12
ptest runs are restored in CI, as a result several ptest related fixes went in, eg. c-ares now have ptests. bpftrace ptests are fixed
Enable Nvidia tegra platforms to build with musl C library, It is limited to headless systems for now. Getting Nvidia GPU drivers to work with musl needs some work. Added a project for orin-nano with SSD instead of uSD
RISCV reference platform VisionFive2 switched to use 6.1 kernel from 5.10

SIOT v0.14.5

simpleiot-js: Fixed bugs and improved README
Replace deprecated io/ioutil functions (#680)
fixed frontend bug where only custom node types could be added

Evaluating NATS Jetstream as a store for Simple IoT

The nats-exp GitHub - simpleiot/nats-exp repo has several experiments where we attempt to determine if we can use NATS Jetstream as a store for Simple IoT. So far, it looks promising.

Time-series metrics:

2024/01/03 14:20:10 NATS TSD experiment
2024/01/03 14:20:10 js.Publish insert rate for 10,000 points: 42028 pts/sec
2024/01/03 14:20:10 js.PublishAsync insert rate for 10,000 points: 412363 pts/sec
2024/01/03 14:20:10 nats.Publish insert rate for 10,000 points: 17937960 pts/sec
2024/01/03 14:20:10 ack: false, Get 30000 points took 0.04, 668062 pts/sec
2024/01/03 14:20:10 ack: true, Get 30000 points took 0.04, 827364 pts/sec
2024/01/03 14:20:10 ack: false, Get 30000 points took 0.03, 881960 pts/sec

Seems fast enough.

Syncing streams between hub and leaf nodes:

[cbrake@quark nats-exp]$ go run ./bi-directional-sync/
=====================================================
       Create stream on hub and source to leaf
=====================================================
* Create stream: server:hub domain:hub stream:NODES-HUB subject:n.hub.>
* Publish: hub -> n.hub.123.value -> 12 13 14 15
* Stream count: server:hub domain:hub stream:NODES-HUB count:4
* Stream count: server:leaf domain:hub stream:NODES-HUB count:4
* Source stream: server:leaf domain:leaf stream:NODES-HUB source-domain:hub subject:n.hub.>
* Stream count: server:leaf domain:leaf stream:NODES-HUB count:4
=====================================================
       Create stream on leaf and source to hub
=====================================================
* Create stream: server:leaf domain:leaf stream:NODES-LEAF subject:n.leaf.>
* Publish: leaf -> n.leaf.456.value -> 22 23 24 25 26
* Source stream: server:hub domain:hub stream:NODES-LEAF source-domain:leaf subject:n.leaf.>
* Stream count: server:hub domain:hub stream:NODES-LEAF count:5
=====================================================
       Shut down leaf node
=====================================================
* Stream count: server:hub domain:hub stream:NODES-LEAF count:5
* Publish: hub -> n.hub.123.value -> 16 17 18 19
* Stream count: server:hub domain:hub stream:NODES-HUB count:8
=====================================================
       Start up leaf node
=====================================================
* Stream count: server:leaf domain:leaf stream:NODES-HUB count:8
* Publish: hub -> n.hub.123.value -> 20 21 22 23
* Stream count: server:leaf domain:leaf stream:NODES-HUB count:12
=====================================================
       Publish more messages to leaf
=====================================================
* Publish: leaf -> n.leaf.456.value -> 27 28 29 30 31
* Stream count: server:leaf domain:leaf stream:NODES-LEAF count:10
* Stream count: server:leaf domain:leaf stream:NODES-LEAF count:10

YAGNI: You Ain’t Gonna Need It and Cake models

YAGNI is a principle that arose from extreme programming which states you should not add functionality until you need it. I learned about this from a recent elm radio episode:

This leads us to two approaches to programming:

The Layered Cake Approach
The Sliced Cake Approach