frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Open in hackernews

Proposal: Add bare metal support to Go

https://github.com/golang/go/issues/73608
85•rbanffy•1y ago

Comments

Someone•1y ago
FTA:

  // printk emits a single 8-bit character to standard output
  //
  //go:linkname printk runtime.printk
  func printk(c byte)
So, printing “Hello, world!”, necessarily will have to make 13 calls to this function. I think I would have required a printk that prints an array of bytes. I expect that can be significantly faster on lots of hardware.

In contrast, there’s

  // getRandomData generates len(b) random bytes and writes them into b
  //
  //go:linkname getRandomData runtime.getRandomData
  func getRandomData(b []byte)
Here, they seem to acknowledge that it can be faster to make a single call.
jeroenhd•1y ago
The method for printing uses an Intel UART driver to print characters. AFAIK, the standard low level UART generally only does single character transfers unless you write a (relatively) complex driver.

Rendering per string is better per string, but I'm not so sure how bad the difference is when it comes to UART but I doubt the system has enough throughput for the first implementation to matter.

90s_dev•1y ago
I wonder if this is related to that bare metal bios os post from a week or so ago. I asked the author why he used tty asm calls to print instead of calling int 10 directly and he said it was more efficient, but for different reasons.

https://news.ycombinator.com/item?id=43873822

Someone•1y ago
> The method for printing uses an Intel UART driver to print characters

The spec (rightfully) says “(e.g. serial console)”, not “Intel UART driver”.

You cannot know what bare metal you’re running on. On some hardware it could be sending data out over Bluetooth, USB or WiFi because that’s the only connection to the outside world.

ronsor•1y ago
Arguably `printk(c byte)` should be `printck(c byte)`, and there should be a separate `printk(s []byte)` that handles an array of bytes.

If `printk` isn't implemented, then fall back to repeated calls of `printck`.

lcarsip•1y ago
printk is the low level primitive for stdout printing and it's done this way as low level drivers generally only accept single characters.

There are upper level functions which simply takes a []byte and make fmt.Printf() work seamlessly and effectively when not printing on an UART that only takes a single character as output.

In TamaGo stdout is primarily used for debugging.

timewizard•1y ago
> Here, they seem to acknowledge that it can be faster to make a single call.

It calls the internal Fill function to fill 4 bytes of the slice at a time. That calls the rng assembly stub function which uses 'rdrand' to get 32bits of random data. Which gets called len(b)/4 times.

I don't think they did it for speed but rather to be more idiomatic.

Anyways, OSDev has had a "Go Bare Bones" page for quite a while:

https://wiki.osdev.org/Go_Bare_Bones

jasonthorsness•1y ago
We use 'scratch' containers for many of our Go applications, so they have no user-space stuff other than our application binary. It reduces exposure for security vulnerabilities. This proposal seems to be taking that approach to the extreme - not even a kernel. Super-interesting; I wonder if it could run on cloud VMs? How tiny could the image become?
jasonthorsness•1y ago
Looks like Tamago targets multiple VM runtimes https://github.com/usbarmory/tamago?tab=readme-ov-file
veggieroll•1y ago
How do you handle temp file space, timezone data, and other things that a minimal image provide?
kfreds•1y ago
Temp file space: Use RAM, or talk to host storage over Virtio.

Timezone data etc: You would have to fetch that over the network, or from a metadata API such as the one Firecracker provides to VM guests.

fpoling•1y ago
Services rarely need timezone done. So if one is OK with supporting only UTC, Go runtime works fine without any timezene data.

We use a minimal image to run in on AWS Nitro VM and it contains only kernel, init.d, the Go application file and TLS certificate roots with the root filesystem mounted over tmpfs.

Note that Nitro VM uses a custom kernel provided by AWS so the new proposal is not relevant for us. But if we could run Go directly in that VM, it will surely makes things faster and saves like 10% memory overhead. And it will also avoid OOM killer and few other bad unwanted interactions between Go runtime and Linux kernel memory management.

champtar•1y ago
For timezones data go already has https://pkg.go.dev/time/tzdata
kfreds•1y ago
> This proposal seems to be taking that approach to the extreme - not even a kernel.

To be fair, there is a kernel - the Go runtime. But since there is no privilege separation it classifies as a unikernel. Performance gains should be expected compared to a system where you have to copy data to/from guest VM kernel space to guest VM user space.

> I wonder if it could run on cloud VMs?

Yes. TamaGo currently runs in KVM guests with the following VMMs: Cloud Hypervisor, Firecracker microvm, QEMU microvm.

> How tiny could the image become?

Roughly the same size as your current Go binary. TamaGo doesn't add much.

ignoramous•1y ago
> To be fair, there is a kernel - the Go runtime.

I like Anil Madhavapeddy's definition for such setups. A compiler that just refuses to stop:

  MirageOS is a system written in pure OCaml where not only do common network protocols and file systems and high-level things like web servers and web stacks can all be expressed in OCaml but the compiler just refuses to stop ... compiler, instead of stopping and generating a binary that you then run inside Linux or Windows, will continue to specialize the application that it is compiling and ... emit a full operating system that can just boot by itself.
https://signalsandthreads.com/what-is-an-operating-system / https://archive.vn/yLfkq
eyberg•1y ago
Cloud vms are a main target for unikernels, however, as Russ mentions in one of the linked issues there actually is quite a lot of other code you need to include in your system depending on what you are deploying to.

For instance systems with arm64 might need UEFI or if you enable SEV now you need additional support for that which is why I'd agree with Russ's stance on this.

Every time someone asks us to provide support for a new cloud instance type (like a graviton 4 or azure's arm) we have to go in and sometimes provide a ton of new code to get it working.

kfreds•1y ago
I assume you're referring to this[1]. I don't think it's necessary to bring all of that into the Go runtime itself, or ask the Go team to maintain it. It would be part of your application, and similar to a board support package.

TamaGo already supports UEFI on x86, and that too would be part of the BSP for your application, not something that would need to be upstreamed to Go proper. Same for AMD SEV SNP.

As for you (nanovms) supporting new instance types, wouldn't it be nice to do that work in Go? :)

Edit: I wonder how big the performance impact would be if you used TamaGo's virtio-net support instead of calling from Go into nanos.

advanderveer•1y ago
I would be interested in this if it enabled deterministic simulation testing for the Go programming languages. There have been some efforts in this area but with little success.
rcarmo•1y ago
I use TinyGo, and it does that job well. Not sure if it’s necessary to mainline it.
lcarsip•1y ago
TinyGo targets an entirely different class of systems and is not something that can be upstream being a different compiler, see https://github.com/usbarmory/tamago/wiki/Frequently-Asked-Qu...

Internet Archive Switzerland

https://internetarchive.ch/
240•hggh•4h ago•27 comments

PipeDream on the Acorn Archimedes

https://stonetools.ghost.io/pipedream-archimedes/
21•msephton•1h ago•4 comments

Google broke reCAPTCHA for de-googled Android users

https://reclaimthenet.org/google-broke-recaptcha-for-de-googled-android-users
1286•anonymousiam•21h ago•468 comments

LLMs Corrupt Your Documents When You Delegate

https://arxiv.org/abs/2604.15597
136•rbanffy•7h ago•46 comments

Using Claude Code: The unreasonable effectiveness of HTML

https://twitter.com/trq212/status/2052809885763747935
305•pretext•11h ago•194 comments

How LEDs are made (2014)

https://learn.sparkfun.com/tutorials/how-leds-are-made/all
65•smig0•2d ago•6 comments

A recent experience with ChatGPT 5.5 Pro

https://gowers.wordpress.com/2026/05/08/a-recent-experience-with-chatgpt-5-5-pro/
492•_alternator_•13h ago•349 comments

Removing fsync from our local storage engine

https://fractalbits.com/blog/remove-fsync/
34•zzsheng•2d ago•14 comments

Mythical Man Month

https://martinfowler.com/bliki/MythicalManMonth.html
263•ingve•2d ago•163 comments

America's carpet capital: an empire and its toxic legacy

https://apnews.com/projects/pfas-forever-stained/
111•rawgabbit•3d ago•53 comments

OpenAI’s WebRTC problem

https://moq.dev/blog/webrtc-is-the-problem/
405•atgctg•1d ago•116 comments

The Intolerable Hypocrisy of Cyberlibertarianism

https://matduggan.com/the-intolerable-hypocrisy-of-cyberlibertarianism/
15•ColinWright•2h ago•1 comments

Making Julia as Fast as C++ (2019)

https://flow.byu.edu/posts/julia-c++
54•d_tr•2d ago•36 comments

GrapheneOS fixes Android VPN leak Google refused to patch

https://cyberinsider.com/grapheneos-fixes-android-vpn-leak-google-refused-to-patch/
44•Georgelemental•1h ago•4 comments

David Attenborough's 100th Birthday

https://www.bbc.com/news/articles/cp3pww9g0p5o
765•defrost•1d ago•148 comments

Reviving the IBM Selectric Composer Fonts (2023)

https://www.kutilek.de/selectric/
36•tangus•2d ago•2 comments

First, the FBI Searched Her Home. Then, She Won a Pulitzer.

https://www.nytimes.com/2026/05/05/business/media/hannah-natanson-washington-post-pulitzer.html
21•mitchbob•1h ago•2 comments

What causes lightning? The answer keeps getting more interesting

https://www.quantamagazine.org/what-causes-lightning-the-answer-keeps-getting-more-interesting-20...
131•Tomte•3d ago•29 comments

Killswitch: Per-function short-circuit mitigation primitive

https://lwn.net/ml/all/20260507070547.2268452-1-sashal@kernel.org/
53•signa11•6h ago•10 comments

Read Programming as Theory Building

https://codeutopia.net/blog/2026/05/09/you-should-read-programming-as-theory-building/
47•birdculture•2h ago•8 comments

Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

https://www.wiisfi.com/
310•homebrewer•3d ago•86 comments

The context window has been shattered: Subquadratic debuts a 12M token window

https://thenewstack.io/subquadratic-12-million-context-window/
14•gmays•51m ago•2 comments

AI is breaking two vulnerability cultures

https://www.jefftk.com/p/ai-is-breaking-two-vulnerability-cultures
378•speckx•22h ago•148 comments

A new hash table for Lwan

https://tia.mat.br/posts/2026/05/06/a-new-hash-table-for-lwan.html
5•g0xA52A2A•2d ago•0 comments

Cartoon Network Flash Games

https://www.webdesignmuseum.org/flash-game-exhibitions/cartoon-network-flash-games
383•willmeyers•23h ago•118 comments

The React2Shell Story

https://lachlan.nz/blog/the-react2shell-story/
191•mufeedvh•23h ago•35 comments

AWS North Virginia data center outage – resolved

https://www.cnbc.com/2026/05/08/aws-outage-data-center-fanduel-coinbase.html
246•christhecaribou•1d ago•175 comments

An Introduction to Meshtastic

https://meshtastic.org/docs/introduction/
475•ColinWright•1d ago•172 comments

Forking the Web

https://dillo-browser.org/lab/web-fork/
72•wrxd•4h ago•63 comments

Teaching Claude Why

https://www.anthropic.com/research/teaching-claude-why
220•pretext•22h ago•110 comments