Memory and Storage Latency

Below you can see memory and storage latencies and their corresponding analogies. For example, a cache miss that triggers a memory access from RAM, is about 100 times slower than the L1 cache. A skilled engineer can make an app run at supersonic speed instead of at a snail's pace — often the difference between a popular app and a dead one.

Component	Latency	Order	Metaphorical Speed
CPU Register	~0.5 ns	1	🚀 3,600 km/h Supersonic jet
L1 Cache	~1 ns	1	✈️ 1,800 km/h Commercial jet
L2/L3 Cache	~ 5 ns	10	🚅 360 km/h High speed train
RAM (DRAM)	~100 ns	100	🛵 18 km/h Scooter
Flash (NOR)	~10 µs	10⁴	🐢 0.18 km/h Tortoise
NVMe SSD	~50 µs	10⁵	🐌 0.036 km/h Snail

Minor, double major or projects

Engineering students often ask, 'Would doing a minor or double major benefit my career?' My answer is that pursuing a minor or double major is a demanding process. Instead, by working on projects related to your field of study, you can achieve much greater benefits with less effort.

Why I unit test

I primarily write unit tests for the following reasons:

1. When I write an algorithm, I almost always miss some edge cases. Writing unit tests helps uncover most of them.
2. Unit testing forces me to maintain clean function interfaces and design modularly.

While it may sometimes feel tedious, the peace of mind that comes with having passing tests is well worth the effort.

Tech trends for software engineers

Yesterday, we had a discussion with software engineering colleagues about Bitcoin and other tech trends. I was asked for my opinion on a current trend that could be profitable to get into. Unsurprisingly, I said AI. By itself, this advice is too vague to be helpful, so I gave a more concrete example: using AI to transform the user interface of apps from menu-based to speech-based. I also pointed them to my Python script that demonstrates the basics of this concept.

As someone who was introduced to computers in the 1980s with the Commodore 64, I have witnessed the rise of Windows, the internet, web apps, mobile apps, and cryptocurrency. This shift toward AI is similar to—and even more dramatic than—when companies started moving to the web during the early days of the internet. 

I understand that creating a new AI model requires billions of dollars and years of research. But the good news is that many of these models provide APIs, which makes them accessible to us mere mortals. We just need to understand a few key concepts, such as:

• How to use AI APIs.
• Which large language models (LLMs) are suitable for offline use.
• How to employ Retrieval-Augmented Generation (RAG) to incorporate data or documents not included in an LLM's training model

As a software engineer, you already possess the most important skills: algorithms, data structures, and programming languages. By spending just a couple of weeks on basic AI topics, you can add another superpower to your skill set. I, for one, will definitely be doing so.

Music: Barış Manço - Şehrazat

Advice for students starting computer engineering

First of all, congratulations on choosing computer engineering as your profession. It’s a challenging field, especially if you currently have limited programming experience. Throughout your studies, you’ll often find yourself juggling at least three demanding courses simultaneously, leaving little time to fully digest the material. You’ll have to move quickly from one assignment or exam to the next, so it’s wise to prepare in advance. Read the blog of one of my computer engineering students to get an idea.

To begin with, it helps to understand the "superpowers" you gain with a computer engineering degree and what they can be used for. No, it’s not just about mobile or web applications. It is applied mathematics. At its core, computer engineering is about solving complex problems with an optimal balance of speed and computer memory usage. For instance, if you can perform a task 40,000 times faster, that’s the difference between the blink of an eye and an hour, or having a popular product or a product no one is using. I recommend the following resources:

• An App Called Napster: A documentary about the impact of advances in computing (MP3 compression and peer-to-peer networking) on the music industry.
• Crash Course Computer Science: A six-hour series covering all the topics you’ll encounter during your four years of study.
• But what is a neural network?: An introduction to artificial neural networks and deep learning.
• The essence of calculus: To prepare for the first year mathematics courses.

If you're having trouble understanding the English in the videos, try watching them at 0.5x speed with captions enabled. You can also use Duolingo to boost your English.

During your holidays, spend a couple of weeks familiarizing yourself with key concepts and gaining the ability to solve simple programming problems. This way, during the semester, you’ll only need to focus on understanding the problems themselves, rather than struggling with basic tasks like how to use a compiler or mastering programming language syntax. Follow CS50x 2024, which covers many computer science/engineering topics. Keep in mind that you’ll need to dedicate at least 20 hours per week to solve the problems in this course.

By laying a solid foundation now, you’ll set yourself up for success in your studies and beyond. Remember, the journey of becoming a computer engineer is demanding but very rewarding. Stay curious, keep challenging yourself, and don't hesitate to seek help when needed. Document your progress and the lessons you learn in a blog. Your dedication and hard work will pay off as you acquire the skills to create innovative solutions. Best of luck on your exciting journey into the world of computer engineering!

Music: Vivaldi's Four Seasons: Summer - Epic Trailer Version

Important vs urgent

In my workplace, we often have more work than we have personnel to handle it. As a technical nerd, I enjoy tackling technical challenges; however, to use my time efficiently, prioritizing tasks is essential. Whenever I receive a request, I assess it based on the following criteria:

1. Is this a bug and does it have significant consequences if not addressed immediately?
2. Is the feature well-defined? Who will be the users, and how will they use it? What value will it bring to them?
3. Will we lose money in the short term (in less than 3 months), if we don't implement it?

If a request satisfactorily meets either criteria 1, or both criteria 2 and 3, I set aside my current tasks and begin working on it. It's important to note that priority/urgency and importance are distinct considerations. I do not simply ask if a feature is "important," as all features hold importance in at least one context.

Surprisingly, few requests meet these criteria. Those that don't are recorded in our tracking system to be revisited later.

Music: Cem Karaca - Emrah (Dedi ki Yok Yok)

How to prepare a good presentation

Most presentations are boring. If you want to make your presentation interesting (assuming you are interested in the topic yourself), do not use any text, only use images or videos. This approach demands more preparation time since you cannot rely on reading from your slides. That's precisely the point because a presentation is not an audio version of a lengthy paper, a leading cause of PowerPoint poisoning. In the limited time available, focus on engaging your audience rather than covering every detail, as striving for completeness can overwhelm your listeners. Quickly captivate their attention and encourage them to pursue more information by asking follow-up questions or exploring additional resources for which you can provide links. The goal is to spark interest, not to deliver an exhaustive lecture. Having absolutely no text in your slides is the simplest way to achieve it.