Is fog computing more efficient than cloud computing? by 
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Advantages of fog: there is only one, reusing hardware that would be otherwise idle.
Disadvantages:
- in cloud, you can put your datacenter on the location with the cheapest possible power. On fog you can't.
- on fog there is some waste due to network communication.
- you will likely optimize code less well because you might be targeting a wide array of different types of hardware, so more power (and time) wastage. Furthermore, some of the hardware used will not not be optimal for the task, e.g. CPU instead of GPU.
All of this makes Ciro Santilli doubtful if it wouldn't be more efficient for volunteers simply to donate money rather than inefficient power usage.
Bibliography:
- greenfoldingathome.com/2018/05/28/is-foldinghome-a-waste-of-electricity/: useless article, does not compare to centralize, asks if folding the proteins is worth the power usage...
They can't even make this basic stuff just work!
Git tips git rebase moves commits one by one by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01In order to solve conflicts, you just have to understand what commit you are trying to move where.
E.g. if from:we do:what happens step by step is first 6 is moved on top of 5:and then 7 is moved on top of the new 6:
5 master
|
4 7 my-feature HEAD
| |
3 6
|/
2
|
1git rebase master6on5 HEAD
|
5 master
|
4 7 my-feature
| |
3 6
| |
2-----------------+
|
17on5 HEAD
|
6on5
|
5 master
|
4 7 my-feature
| |
3 6
| |
2-----------------+
|
17on5 my-feature HEAD
|
6on5
|
5 master
|
4
|
3
|
2
|
1 Git tips How to modify the commit tree by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01 AWS Deep Learning Base GPU AMI (Ubuntu 20.04) by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01These come with pre-installed drivers, so e.g. nvidia-smi just works on them out of the box, tested on g5.xlarge which has an Nvidia A10G GPU. Good choice as a starting point for deep learning experiments.
Large but ephemeral storage for EC2 instances. Predetermined by the EC2 instance type. Stays in the local server disk. Not automatically mounted.
- docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html (archive) notably highlights what it persists, which is basically nothing
- serverfault.com/questions/433703/how-to-use-instance-store-volumes-storage-in-amazon-ec2 mentions that you have to mount it
Amazon's informtion about their own intances is so bad and non-public that this was created: instances.vantage.sh/
Git tips How to visualize the commit tree by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Generate a minimal test repo. You should get in the habit of doing this to test stuff out.
#!/usr/bin/env bash
mkdir git-tips
cd git-tips
git init
for i in 1 2 3 4 5; do
echo $i > f
git add f
git commit -m $i
done
git checkout HEAD~2
git checkout -b my-feature
for i in 6 7; do
echo $i > f
git add f
git commit -m $i
doneBy default, LSF only sends you an email with the stdout and stderr included in it, and does not show or store anything locally.
One option to store things locally is to use:as documented at:
bsub -oo stdout.log -eo stderr.log 'echo myout; echo myerr 1>&2'Or to use files with the job id in them:
bsub -oo %J.out -eo %J.err 'echo myout; echo myerr 1>&2'By default as mentioned at:
bsub -oo:To get just the stdout to the file, use
bsub -N -oo which:- stores only stdout on the file
- re-enables the completion email
Another option is to run with the bsub This immediately prints stdout and stderr to the terminal.
-I option:bsub -I 'echo a;sleep 1;echo b;sleep 1;echo c' Git tips Linear history vs branching by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Some people like merges, but they are ugly and stupid. Rebase instead and keep linear history.
Linear history:
5 master
|
4
|
3
|
2
|
1 first commitBranched history:
7 master
|\
| \
6 \
|\ \
| | |
3 4 5
| | |
| / /
|/ /
2 /
| /
1/ first commitWhich type of tree do you think will be easier to understand and maintain?
????
????????????
You may disconnect now if you still like branched history.
Git tips Merge two or more commits into one by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01 Git tips The key to solve conflicts: see the two conflicting diffs by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01The key to solve conflicts is:
You have to understand what are the two commits that touched a given line (one from master, one from features), and then combine them somehow.
Git tips Understand the commit tree by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01This is the most important thing to understand Git!
You must:
- be able to visualize the commit tree
- understand how each git command modifies the commit DAG
Pinned article: ourbigbook/introduction-to-the-ourbigbook-project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact