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Browse S3 bucket on web browser by

Ciro Santilli 37 Updated 2025-07-16

They can't even make this basic stuff just work!

stackoverflow.com/questions/16784052/access-files-stored-on-amazon-s3-through-web-browser

Amazon Elastic Compute Cloud by

Ciro Santilli 37 Updated 2025-07-16

Amazon EC2 HOWTO by

Ciro Santilli 37 Updated 2025-07-16

Amazon EC2 hello world by

Ciro Santilli 37 Updated 2025-07-16

Let's get SSH access, instal a package, and run a server.

As of December 2023 on a t2.micro instance, the only one part of free tier at the time with advertised 1 vCPU, 1 GiB RAM, 8 GiB disk for the first 12 months, on Ubuntu 22.04:

$ free -h
               total        used        free      shared  buff/cache   available
Mem:           949Mi       149Mi       210Mi       0.0Ki       590Mi       641Mi
Swap:             0B          0B          0B
$ nproc
1
$ df -h /
Filesystem      Size  Used Avail Use% Mounted on
/dev/root       7.6G  1.8G  5.8G  24% /

To install software:

sudo apt update
sudo apt install cowsay
cowsay asdf

Once HTTP inbound traffic is enabled on security rules for port 80, you can:

while true; do printf "HTTP/1.1 200 OK\r\n\r\n`date`: hello from AWS" | sudo nc -Nl 80; done

and then you are able to curl from your local computer and get the response.

Lorentz invariant by

Ciro Santilli 37 Updated 2025-07-16

Basically a synonym of Lorentz covariance?

Amazon EC2 GPU by

Ciro Santilli 37 Updated 2025-07-16

As of December 2023, the cheapest instance with an Nvidia GPU is g4nd.xlarge, so let's try that out. In that instance, lspci contains:

00:1e.0 3D controller: NVIDIA Corporation TU104GL [Tesla T4] (rev a1)

so we see that it runs a Nvidia T4 GPU.

Be careful not to confuse it with g4ad.xlarge, which has an AMD GPU instead. TODO meaning of "ad"? "a" presumably means AMD, but what is the "d"?

Some documentation on which GPU is in each instance can seen at: docs.aws.amazon.com/dlami/latest/devguide/gpu.html (archive) with a list of which GPUs they have at that random point in time. Can the GPU ever change for a given instance name? Likely not. Also as of December 2023 the list is already outdated, e.g. P5 is now shown, though it is mentioned at: aws.amazon.com/ec2/instance-types/p5/

When selecting the instance to launch, the GPU does not show anywhere apparently on the instance information page, it is so bad!

Also note that this instance has 4 vCPUs, so on a new account you must first make a customer support request to Amazon to increase your limit from the default of 0 to 4, see also: stackoverflow.com/questions/68347900/you-have-requested-more-vcpu-capacity-than-your-current-vcpu-limit-of-0, otherwise instance launch will fail with:

You have requested more vCPU capacity than your current vCPU limit of 0 allows for the instance bucket that the specified instance type belongs to. Please visit aws.amazon.com/contact-us/ec2-request to request an adjustment to this limit.

When starting up the instance, also select:

image: Ubuntu 22.04
storage size: 30 GB (maximum free tier allowance)

Once you finally managed to SSH into the instance, first we have to install drivers and reboot:

sudo apt update
sudo apt install nvidia-driver-510 nvidia-utils-510 nvidia-cuda-toolkit
sudo reboot

and now running:

nvidia-smi

shows something like:

+-----------------------------------------------------------------------------+
| NVIDIA-SMI 525.147.05   Driver Version: 525.147.05   CUDA Version: 12.0     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|                               |                      |               MIG M. |
|===============================+======================+======================|
|   0  Tesla T4            Off  | 00000000:00:1E.0 Off |                    0 |
| N/A   25C    P8    12W /  70W |      2MiB / 15360MiB |      0%      Default |
|                               |                      |                  N/A |
+-------------------------------+----------------------+----------------------+

+-----------------------------------------------------------------------------+
| Processes:                                                                  |
|  GPU   GI   CI        PID   Type   Process name                  GPU Memory |
|        ID   ID                                                   Usage      |
|=============================================================================|
|  No running processes found                                                 |
+-----------------------------------------------------------------------------+

If we start from the raw Ubuntu 22.04, first we have to install drivers:

From there basically everything should just work as normal. E.g. we were able to run a CUDA hello world just fine along:

nvcc inc.cu
./a.out

One issue with this setup, besides the time it takes to setup, is that you might also have to pay some network charges as it downloads a bunch of stuff into the instance. We should try out some of the pre-built images. But it is also good to know this pristine setup just in case.

We then managed to run Ollama just fine with:

curl https://ollama.ai/install.sh | sh
/bin/time ollama run llama2 'What is quantum field theory?'

which gave:

0.07user 0.05system 0:16.91elapsed 0%CPU (0avgtext+0avgdata 16896maxresident)k
0inputs+0outputs (0major+1960minor)pagefaults 0swaps

so way faster than on my local desktop CPU, hurray.

After setup from: askubuntu.com/a/1309774/52975 we were able to run:

head -n1000 pap.txt | ARGOS_DEVICE_TYPE=cuda time argos-translate --from-lang en --to-lang fr > pap-fr.txt

which gave:

77.95user 2.87system 0:39.93elapsed 202%CPU (0avgtext+0avgdata 4345988maxresident)k
0inputs+88outputs (0major+910748minor)pagefaults 0swaps

so only marginally better than on P14s. It would be fun to see how much faster we could make things on a more powerful GPU.

Amazon Machine Image by

Ciro Santilli 37 Updated 2025-07-16

Neovius surface by

The Neovius surface refers to a specific type of mathematical surface that has properties useful in the study of differential geometry and topology. It is named after the Finnish mathematician A.F. Neovius, who studied the surface and its properties. The Neovius surface is typically characterized by its complex structure, including features like cusps and self-intersections, making it interesting from the perspectives of both geometry and mathematical physics.

List of AWS AMIs by

Ciro Santilli 37 Updated 2025-07-16

Supergeometry by

Supergeometry is a branch of mathematics that extends the concepts of geometry to include both geometric structures and "supersymmetrical" objects, which involve odd or "fermionic" dimensions. It arises from the study of supersymmetry in theoretical physics, where it plays a crucial role in string theory and quantum field theory. In conventional geometry, one typically works with spaces that are defined by traditional notions of points and curves in even-dimensional Euclidean spaces.

Synthetic differential geometry by

Synthetic Differential Geometry (SDG) is a branch of mathematics that provides a framework for differential geometry using a synthetic or categorical approach, rather than relying on traditional set-theoretic and analytical foundations. This approach is particularly notable for its use of "infinitesimals," which are small quantities that can be treated algebraically in a way that is similar to how they are used in non-standard analysis.

Tangential angle by

The term "tangential angle" can refer to different concepts depending on the context, but it generally relates to the angle formed by a tangent line to a curve or surface. Here are a couple of specific interpretations: 1. **In Geometry**: The tangential angle can refer to the angle between a tangent line (a line that just touches a curve at a single point) and the horizontal axis (or another reference line).

Disc theorem by

The Disc theorem is a concept in complex analysis and deals with the behavior of holomorphic functions. Specifically, it is related to the area of function theory. While there are various formulations and different contexts in which the term "Disc theorem" might be used, one specific interpretation often referenced involves properties related to holomorphic functions defined on the unit disk in the complex plane.

Generalized Stokes theorem by

The Generalized Stokes' Theorem is a fundamental result in differential geometry and vector calculus that extends the classical Stokes' theorem, relating integrals of differential forms over manifolds to their behavior on the boundaries of those manifolds. It serves as a powerful tool in various fields such as physics, engineering, and mathematics, particularly in the study of differential forms, topology, and manifold theory.

Kervaire invariant by

The Kervaire invariant is a concept in algebraic topology, specifically in the study of bordism theory and the classification of high-dimensional manifolds. It is named after the mathematician Michel Kervaire, who introduced it in the context of differentiable manifolds. More formally, the Kervaire invariant is a specific invariant associated with a smooth manifold, particularly focusing on the topology of the manifold's tangent bundle.

Sphere eversion by

Sphere eversion is a process in topology, a branch of mathematics, where a sphere is turned inside out in a continuous manner without creating any creases or tears. The concept involves smoothly deforming a spherical surface so that its inside becomes its outside.

Complex geodesic by

In the context of differential geometry and complex analysis, a **complex geodesic** typically refers to a generalization of the concept of a geodesic in the realm of complex manifolds or complex spaces. The classical notion of a geodesic is a curve that is locally a distance minimizer between points in a given space. In Riemannian geometry, geodesics are trajectories that exhibit extremal properties (typically, minimizing lengths) in a curved space.

Static spacetime by

Static spacetime is a concept in general relativity that refers to a type of spacetime geometry that is both time-independent (static) and has a specific symmetry. More formally, a static spacetime is one where the gravitational field does not change over time and exhibits certain symmetries, particularly time translation symmetry and spatial symmetry. Key characteristics of static spacetimes include: 1. **Time Independence**: The metric tensor, which describes the geometry of spacetime, does not vary with time.

Serge Rudaz by

Serge Rudaz is a philosopher, filmmaker, and writer known for his contributions to discussions on philosophy, ethics, and the intersection of these fields with cinematic narratives. His work often explores the impact of media on societal values and individual perception.