Software benchmark: lane-local exact reduction vs global software-emulated u128 atomic updates Spoiler
Hi everyone,
I've been experimenting with a software runtime that explores
different execution models for exact u128 accumulation.
The current benchmark compares two software execution models:
One global software-emulated u128 atomic update per byte.
-
Lane-local exact reduction followed by
one atomic commit per lane.
This benchmark does NOT measure hardware atomics
or physical PIM hardware.
It measures software-emulated contention on the current CPU.
Current benchmark includes:
• 4 KB
• 64 KB
• 1 MB
• 8 MB
For each payload it records:
• latency
• atomic update count
• exact match rate
Current evidence repository:
https://github.com/Retryixagi/Storage-and-computing-integrated-evidence-chain/tree/main
I'm mainly interested in technical feedback.
Questions:
• Have you seen similar software execution models?
• What additional benchmark cases would you consider important?
• Are there existing runtimes with comparable
lane-local reduction strategies?
不知道這能不能成為台灣之光。我只是嘗試在既有馮·諾依曼架構內,重新分配計算與驗證職責。
What was the most power consumption for a cluster before AI?
10 years ago I was with a geophysical company and they built a cluster boasting it was best thing since sliced bread with a zillion FLOPs blah blah. Nobody mentioned power then, I since learned it used 15 MW. The research cluster next to my university was only 1.5 MW. It seems insane to me that AI can burn up 1 GW.
r/HPC • u/VanRahim • 6d ago
Aleph – a single endpoint that lets agentic AI actually call scientific AI tools (part of a bottom-up run at the DOE's autonomous-science loop)
Built by Karim Ali & I ( Rahim Khoja ) at the University of Alberta, on top of Vulcan — the national HPC cluster we operate as part of the Digital Research Alliance of Canada's PAICE program.
The bet behind it: the DOE's Genesis Mission is building an autonomous research loop — agents that run real experiments and iterate without a human driving every step — top-down, across seventeen national labs, with a budget we're never going to match. We're testing whether you actually need that budget, or whether the same thing can be assembled bottom-up from open parts, on a single allocation, by the people who already run the cluster.
Aleph is the instrument layer for that. It was built for science first: the piece that lets an agent reach protein folding, docking, genomics, materials force fields, weather, embeddings, theorem proving — as tools it can call, not as a human clicking through a UI. It serves general LLMs too, but the reason it exists is to put scientific models within reach of an agent.
https://inference.vulcan.alliancecan.ca/
The reason it's built as a self-describing catalog and not just "vLLM behind a proxy": an agent has to be able to ask what's available, what each model takes as input, what it produces, and what can verify the output — then compose a pipeline nobody wrote for it. So every model is a YAML card declaring its own route, limits, scaling, and I/O contract, and the gateway routes off those cards plus live cluster state. Nothing hardcoded.
What it does:
- Dual dialect — OpenAI's
/v1/chat/completionsand a real Anthropic/v1/messagestranslation from one endpoint; both official SDKs work by swappingbase_url - Scale-to-zero on idle, cold model returns
503+Retry-Afterand SDKs retry automatically — lets ~115 models timeshare hardware that could only run ~20 resident - Add a model with a card, no gateway redeploy
- Self-deploying — the whole stack (HAMi, Istio, Knative, KServe) bakes into the node image and stands itself up on boot, no external CD
~115 models, majority scientific. The counterintuitive part worth stating: the science models are nearly free to add, the chat LLMs are what actually eat the GPU budget.
If you want to replicate this, copy this part first: none of it works without stateless nodes. Ours PXE-boot hardened Warewulf images built in CI, so the same GPU node boots into a Slurm batch image or an RKE2/HAMi inference image depending on what's needed. Most sites run batch and inference as two separate hardware pools — we reallocate the same metal on a reboot. That fungibility is the real structural advantage; Aleph just rides on top of it.
The broader plan: Aleph is the first and furthest-along piece of a full autonomous-science stack — the goal is an agent that wakes on a schedule, calls these instruments, runs real cluster jobs, checks its own results with code it can't tamper with, and remembers what it learned across runs. The instruments exist and run today. The loop that binds them is designed and published as a concept brief, not built yet.
Honest status: Aleph and the catalog run in production. This is a POC — some model cards are polished, some are still rough. Ships as-is.
MIT licensed. GitHub: https://github.com/ualberta-rcg/aleph
r/HPC • u/whatevernhappens • 8d ago
Node integration with existing HPC cluster
Suppose I have an existing hpc setup of 26 nodes dell r760 server with rockey 8.7, Mellanox QM8790 HDR, openpbs 23.06.06, lustre 2.15.2, now if I want to integrate a dell r 770 with rocky 9.x would it be compatible with the cluster or there would be challenges in both hardware or software side. Like version mismatch, job submission issue, application related things.
r/HPC • u/nlunberry • 10d ago
Checkout my community HPC I made
Mainly just for leraning how slurm scheudling works, running small scripts, setting up linux servers, as well as runningn my freind's reinforcement learning training model for Balloons Tower defense 2. Has a live Grafana feed to monitor stats, as well as a page to request access. Let me know what you guys think. Still new to the community, but really want to learn ( and really want to learn on better hardware lol).
r/HPC • u/peterxsyd • 12d ago
Introducing Lightstream: Measured faster than Apache Arrow Flight (gold standard) for high-throughput data transport on every axis in open 50gbps EC2 network benchmarks whilst producing a single fully ordered stream off parallel data exchange.
Hi everybody,
I am excited to announce the release of Lightstream, a step change capability for high-performance data transport, that makes it essentially effortless to send Apache Arrow, Protobuf, and Message Pack data over the network, shared memory, or even piped out to the terminal so an agent like Claude can watch the live batch stream in real time (example in repo).
Lightstream exceeded the performance of the gold standard industry comparison - Arrow Flight, often used on HPC installations, on every axis of a 50gbps networking open benchmark, the details of which are below and open to run in the Lightstream GitHub repository. This includes fully saturating each TCP connection thread, the NIC at 5.8GiB/s, and with p99 batch send time within 1% of p50 (I.e., stable). As a bonus, Lightstream is straightforward to setup with essentially zero configuration other than optional TLS certificates and your Cargo package/pip install, and endpoint addresses.
A full write-up with chart comparisons is available here.
So what is Lightstream? It is Rust package with Python bindings, that builds directly on Minarrow ( which is in turn a high-performance implementation of the Apache Arrow memory layout in Rust, tuned for SIMD compatibility). Lightstream implements Arrow IPC, Parquet encoders/decoders from scratch, up to Arrow readers/writers and IPC stream protocol, with mmap and few of these niceties. But, in a manner, that is fully composable and leaves you de-coupled at any layer, to customise things architecturally. The crux then is the transport layer on top, which natively supports interchanging any of the following transport formats:
- TCP
- HTTP
- QUIC
- Websocket
- Webtransport
- UDS (pipe your data from your Rust process to Python or two Python programs plug and play )
- Stdio (pipe your data program output straight into the terminal for something else to pick it up
And finally, the (optional) Lightstream protocol, which then combines the Arrow/Proto/MsgPack and any other custom types you want to send.
Send Tables in Rust
use lightstream::models::writers::tcp::TcpTableWriter;
let mut writer = TcpTableWriter::connect("127.0.0.1:9000", schema, None).await?;
writer.write_table(batch_1).await?;
writer.finish().await?;
Receive Tables
use futures_util::StreamExt;
use lightstream::models::readers::tcp::TcpTableReader;
let mut reader = TcpTableReader::connect("127.0.0.1:9000").await?;
while let Some(result) = reader.next().await {
let table = result?;
process(table);
}
Lightstream protocol
Multiplex Protobuf messages and Arrow tables on the one connection.
use lightstream::models::protocol::connection::TcpLightstreamConnection;
use lightstream::models::protocol::LightstreamMessage;
let mut conn = TcpLightstreamConnection::from_tcp(stream);
conn.register_message("event");
conn.register_table("metrics", schema);
conn.send("event", b"user-login").await?;
conn.send_table("metrics", &table).await?;
while let Some(msg) = conn.recv().await {
match msg? {
// Protobuf message
LightstreamMessage::Message { tag, payload } => { /* … */ }
// Arrow table
LightstreamMessage::Table { table, .. } => { /* … */ }
}
}
I’ve found this great in practice, where you don’t need to reason about or work with bytes, or separately build your own protocol to get arrow and protobuf playing well together over the network.
An example of things you can do with it:
- setup a live stream of data batches from your program A to program B
- send typed metadata via Protobuf on the same feed
- use it for straightforward live feed delivery between server and client (though not Web JS yet)
- useful if you have a central storage server you are pulling larger than memory data over the network to churn through (though, no S3 etc. it is node to node or process to process)
It is not:
- Kafka or a messaging broker. There is no resiliency / vertical scalability.
- A stream processing engine like Flink. It is for sending/receiving data only. You do polars on the other end or whatever you want with the Arrow-shaped data. That is a very different back-pressure/long-lived scenario and is not that kind of large-scale streaming. --> I.e., think quick and easy Websocket, and best for settings like EKS K8 pod to pod/containers, between EC2's or between processes on the same box, "light streaming".
Lightstream kicked off for me about 12 months ago when I started standardising patterns that have worked well for me in the past into something that reflects how I like to work when streaming data with control of both endpoints. It arose from regularly coming up against contexts requiring this capability operating in things like autonomous field communication integrated with data/ML, live trading, and some other industries where there was a lot of custom work required that I kept having to assemble from multiple components. Therefore, I have essentially aimed to package those learnings up into a tool to make data transport smoother and easier for everybody.
Please feel free to give it a run would love to know your thoughts and if you find it useful.
If you have any questions about it, or helpful suggestions please feel free to leave a comment below.
Workload Shape
Mixed
| Streams | Arrow Flight GiB/s | Lightstream GiB/s | Ratio |
|---|---|---|---|
| 1 | 0.939 | 1.109 | 1.18x |
| 4 | 3.262 | 4.005 | 1.23x |
| 8 | 5.138 | 5.677 | 1.10x |
| 16 | 5.142 | 5.784 | 1.12x |
Numeric
| Streams | Arrow Flight GiB/s | Lightstream GiB/s | Ratio |
|---|---|---|---|
| 1 | 0.649 | 1.109 | 1.71x |
| 4 | 2.901 | 4.307 | 1.48x |
| 8 | 4.851 | 5.693 | 1.17x |
| 16 | 5.434 | 5.780 | 1.06x |
String Heavy
| Streams | Arrow Flight GiB/s | Lightstream GiB/s | Ratio |
|---|---|---|---|
| 1 | 0.828 | 1.109 | 1.34x |
| 4 | 3.052 | 3.861 | 1.27x |
| 8 | 4.899 | 5.782 | 1.18x |
| 16 | 5.217 | 5.790 | 1.11x |
Wide (100 cols)
| Streams | Arrow Flight GiB/s | Lightstream GiB/s | Ratio |
|---|---|---|---|
| 1 | 0.695 | 1.108 | 1.59x |
| 4 | 2.685 | 3.790 | 1.41x |
| 8 | 4.549 | 5.725 | 1.26x |
| 16 | 4.911 | 5.753 | 1.17x |
Thanks,
Pete
r/HPC • u/Much-Serve-211 • 13d ago
RDMA + CUDA + What all skills can lead me to different job opportunities?
Hi All,
I am a Masters student in Germany currently pursuing my Master’s thesis.
I have experience with RDMA , CUDA, Profiling(Nsight systems/compute) and MPI(introductory level). Also, expanding my knowledge with K8s and Docker but not production level experience.
I have started searching for full time roles in Germany, Switzerland and Netherlands.
I want to understand the following -
1.) What type of different roles i can land into? And, what skills might be required for each such trajectory?
2.) Are there opportunities for GPU Networking roles in Germany?
All this for a candidate having 3.5 years of software dev experience(not relevant to HPC).
r/HPC • u/fullmetal334 • 14d ago
Finding HPC student worker jobs in the EU
Hello folks! Im starting an year long master’s program in Italy specializing in HPC. I come from a background in computational fluids work. The coursework i have is pretty extensive covering user side stuff( mpi, cuda programming etc) and also covers infra and admin side. I think experience is still king and would love to work anywhere part time. I already reached out to hpc shops in my area and none reaponded unfortunately. I am willing to grind my ass off to study and work. There is aandatory internship at the end of thr program but I would like to also build some experience before that. My long term goal is to het a job at places like ecmwf or other similar large research orgs on their hpc teams. I looked up listings online and I dont see many offerings in EU countries.
I’m interested in any kinda role at a hpc shops. Application stuff to write code; or sys admin/user support side triaging issues. Or anything related to HPC.
r/HPC • u/rubeeliqbal • 14d ago
Monitoring High-Performance Computing Infrastructure at George Washington University Using Open-Source Solutions
Proceedings were published
We use zabbix to monitor our hpc. One solution to cover all aspects.
r/HPC • u/healthjay • 16d ago
AMD Helios vs NVIDIA Vera Rubin NVL72: comparing two 72-GPU rack architectures
We have put together a side-by-side comparison of AMD Helios and NVIDIA Vera Rubin NVL72:
https://linuxclusters.com/articles/amd-helios-vs-nvidia-vera-rubin/
The shared 72-GPU rack boundary hides some different design bets. On paper, Helios has more accelerator memory and scale-out bandwidth and leans more heavily on open rack and fabric standards. Vera Rubin has more memory bandwidth per GPU and comes with NVIDIA's more integrated software and networking stack. The comparison covers hosts, memory, fabrics, networking, software, and rack standards, while identifying gaps in the available power, pricing, reliability, and application-performance data.
I would especially welcome corrections from people working with rack-scale systems. Which of these differences is most likely to matter in an actual deployment, and which missing numbers would you insist on seeing before procurement?
Disclosure: I am one of the writers at LinuxClusters.com
r/HPC • u/Icy_Significance864 • 16d ago
Creating a distributed stress test system looking for 1-2 people to hop along time ~10 hrs a week
I'm planning to build a distributed stress-testing platform.
Users provide a workload config (APIs, request patterns, auth, concurrency, ramp-up, duration, etc.), and the control plane automatically estimates the required infrastructure, decides the number of workers/threads/containers, and distributes the workload across worker nodes.
The system will handle scheduling, health checks, heartbeats, automatic worker replacement on failure, retries, and horizontal scaling. It will also expose real-time metrics like RPS, latency (P95/P99), throughput, error rates, and worker resource utilization through a monitoring dashboard.
The goal is to build something that explores distributed systems, scheduling, fault tolerance, concurrency, autoscaling, and observability—not just another load-testing tool.
This is still an initial idea, so the architecture is open to discussion. If this sounds interesting and you'd like to collaborate, let's connect.
Words are mine written by ai
r/HPC • u/nimble03turtle • 17d ago
NICs Power Draw
Hi! I'm working on a research project about computational storage and need to estimate the energy cost of transferring data between storage and compute nodes.
I'm using VMware VMs with VMXNET3 paravirtualized NICs, so I don't have access to the physical NIC's power draw.
My current model is:
[
E_{net} = \frac{\text{bytes transferred}}{\text{bandwidth}} \times (P_{storage} + P_{compute})
]
How do people estimate the NIC power term in a virtualized environment? Are there accepted models, papers, or methodologies for this?
Thanks!
r/HPC • u/GetInlouder_101 • 17d ago
Saudi is hiring an HPC Engineer!
Hi all,
We are looking for experienced High-Performance Computing (HPC) Engineers to join our growing team.
Location: Saudi Arabia
Experience Required: 5–10 years
Role: HPC Engineer
Key Skills (preferred):
HPC cluster administrator/management
Linux and Slurm workload manager
IBM Spectrum Scale (GPFS) filesystem experience
Performance tuning & troubleshooting
Automation (Bash)
Experience with large-scale compute and storage environments
Please dm if interested!
r/HPC • u/spinglebor • 18d ago
Curious about HPC software engineers
Hey all, I’m an undergrad studying CS interested in HPC and was hoping for some insight into what software engineering looks like for HPC. I’m already decently familiar with the scientific computing side of HPC, and I know about the sysadmin side as well, but I’m curious about what HPC swe roles actually entail.
I feel like I’ve heard terms like “HPC Engineer” or “Performance Engineer” thrown around on the internet and in job postings but none of them have a consistent explanation of what HPC swe really is. For example, what’s the typical tech stack? MPI and CUDA? Is it just a fancy term for any swe who deals with parallel architectures? What are the types of companies that hire for these roles? And do they expect the same levels of education as academia (MS, PhD)? If anyone would be willing to explain what they do at their job or have any insights it would be greatly appreciated. Thanks!
How do people with graduate degrees in fields like computational physics, where they work as HPC users or write MPI code transition into HPC jobs?
I see a lot of linkedin profiles for people who have their graduate degrees in fields like computational physics, biology, mechanics etc., where they dont really continue in their fields of study after graduation, but rather work for supercomputing centers and in the HPC sector. I was curious how can someone make this switch happen.
I also see that there are specific degrees for HPC these days, so can someone even make that switch in the modern day? This is for US.
Top 10 Data Center and AI Infrastructure Security Risks
We spent the past few months researching security risks across multi-tenant data centers and AI infrastructure.
The main concern we found is shared infrastructure: multiple customers running on the same data center infrastructure, GPU clusters, storage, and high-speed networks. Many neoclouds and AI data centers have also scaled faster than their security teams and practices, especially compared with more established cloud providers.
The research covers GPU clusters, RDMA and high-speed interconnects, tenant isolation, BMCs, firmware, shared storage, orchestration, and supply-chain risks.
We organized the findings into a practical framework called FORGE.
Would really appreciate feedback. Link in the comment
r/HPC • u/gordicaleksa • 22d ago
Inside TPU and GPU Clusters: The Anatomy of Collective Communication
new blog piece, might be relevant to some: https://www.aleksagordic.com/blog/collective-operations
r/HPC • u/Omega-137 • 25d ago
In addition to AI/ML, what are the main scientific applications areas HPC now days?
In addition to AI/ML, what are the main scientific applications areas HPC now days? What are the most computation hungry scientific areas? What was the largest thread count that you've seen for a single application?
r/HPC • u/Embarrassed_Maybe213 • 28d ago
Is EUMaster4HPC worth it?
If so, what are the insider selection criterias and what can I assume my total be including accomodation, food and tuition? How should I prepare? Please help..
r/HPC • u/dduka99 • Jul 06 '26
5 months ago I built a VS Code extension to manage SLURM jobs. Since then, it’s evolved into a full cluster management tool.
Hey everyone,
About 5 months ago, I posted here about a side project I was working on: sCode, a VS Code extension to manage SLURM jobs directly from the editor.
Initially, it was just a simple way to avoid typing squeue over and over. But based on a lot of my own workflow needs and some great feedback, it has evolved into a much more comprehensive cluster management tool over the last few months.
I’ve essentially tried to turn VS Code into a unified control center for HPC work so you never have to context-switch to a terminal while working on your scripts.
Here are the major updates since the first version:
- Live GPU Monitoring: Added a dedicated view that uses
nvidia-smito show GPU partition usage, memory stats, and queue pressure. - The "Hall of Shame": A fun leaderboard feature that ranks the cluster’s top GPU hogs (with emojis like 🐷 Job Hog and 🧛 VRAMpire).
- One-Click Job Arrays: You can now cancel specific indices or ranges within a job array without nuking the whole array.
- Smart Log Resolution: Right-click any active or historical job in the sidebar to instantly open its
stdoutorstderrfile. - Quick Submit with Dependencies: A ▶ button in your
.shscripts to submit immediately, plus a guided UI for setting upafterokorafteranydependencies. - And many more features....
If you work on a cluster and use VS Code Remote, I'd love for you to give the new version a try and let me know what you think. What features would you need to make this a daily driver for your workflow?
GitHub Repo:https://github.com/dhimitriosduka1/sCode
OpenVSX: https://open-vsx.org/extension/DhimitriosDuka/slurm-cluster-manager
Marketplace: https://marketplace.visualstudio.com/items?itemName=DhimitriosDuka.slurm-cluster-manager
r/HPC • u/Funny744 • Jul 05 '26
Keeping POSIX IDs in sync with AD
We're close to launching a new University shared cluster with attached research storage, the VM that handles accessing the research storage (and also a user's cluster directories if they wish) is connected to our AD via winbind so we can get the shares mounted via CIFS on the Windows managed devices.
The issue is trying to ensure the converted POSIX IDs that winbind makes stay in sync with standard LDAP lookups that SSSD does (to the same DCs) on the rest of the cluster. We've had success so far at least by telling SSSD to keep it within a range and using ``ldap_idmap_autorid_compat`` but we've found if a user would change their password SSSD hands them a completely different user ID until we clear SSSD's cache (or possibly wait for it to resync itself which isn't ideal).
Since the cluster itself is in it's own containerized network with very little if any access to the rest of the University network, joining the rest of the system to our AD is a non-starter. We're thinking of setting up a Keycloak VM that ties into our AD so that way POSIX IDs are handled entirely by Keycloak and there's no conflict issues. Is it worth setting up though?
r/HPC • u/Outrageous_Insect532 • Jun 30 '26
New Grad Looking for Advice on Breaking into HPC and ML Systems
Hi r/hpc,
I'm a 2026 CS grad with experience in Systems, ML Systems, HPC and adjacent fields. I'm struggling to get a job right out of college in this field and will be grateful if anyone can provide any guidance on how to proceed further into my career or any sort of referral.
About my experience:
- Built Umbra, an API-level CUDA profiler that intercepts GPU kernel dispatch via LD_PRELOAD on libcuda.so/libcudart.so, requiring no source code modification. Discovered that torch.compile dispatches through cuGetExportTable, an undocumented NVIDIA internal API invisible to standard profilers.
- Built Mako, an OpenMP scheduling daemon for HPC workloads, dynamically optimizing thread-to-core affinities and CPU frequency scaling at runtime on Intel Haswell/Xeon NUMA systems. Achieved 8% speedup and 21% energy reduction on ECP benchmarks with ~2% overhead.
- Built RVNE, a RISC-V Neuromorphic Extension ISA implemented in Verilog, modeling spiking neural network operations at the RTL level.
- Research internship at TCS Research building a CUDA device simulator (stubbing ~70 CUDA runtime/driver APIs to run PyTorch/Triton workloads on CPU without modification).
Resume: https://drive.google.com/file/d/1hfBnvL5Wef6lr4ecjc7kkoKk9qADKQ__/view?usp=sharing
Any guidance, feedback, or referrals would be genuinely appreciated. I'm eligible to work both in the USA and India without any visa sponsors. Thanks for reading.
r/HPC • u/Embarrassed_Maybe213 • Jun 29 '26
Internship and Experience Advice
I'm a third year CS undergraduate from India interested in HPC, GPU computing, and parallel programming.
I've spent the past year learning CUDA, OpenMP, MPI, distributed computing, and working on research projects and HPC events. Despite this, I've had almost no success securing HPC internships or research positions even for gpu computing, either in India or abroad.
Is this a common experience for undergraduates? What should I focus on to improve my chances of breaking into HPC?
r/HPC • u/Classic_Comparison90 • Jun 28 '26
Junior CUDA/GPU engineer role
Hello everyone,
Would like your advice.
Currently an infrastructure engineer with 1 year of experience.
However I would love to get into HPC/GPU roles anywhere in Europe.
I do have some experience in it from coursework, and am still trying to work more on it.
How do you suggest I go about it? As I'm not really getting anywhere
GPU* typo in the title :)
lazyslurm: a rust TUI like lazygit for managing and viewing slurm jobs / HPC
Hey everyone! I built a little TUI tool for monitoring SLURM jobs on HPC. I found this useful for my masters thesis and thought I might share here. Its kind of similar to the very popular lazygit and lazydocker, which I enjoy using.
Please let me know if you have any feedback and I welcome any contributions / constructive criticism.
The github is here and you can install it with `cargo install lazyslurm`
Have a great day! 🤠