Chapter 102 - 99: Engineering Academician, Gao Wen
Yan University, School of Information Science and Technology.
A large multimedia lecture hall in the Science Building was packed to the rafters.
Not only were extra seats crammed into the aisles, but even the empty space at the back and the windowsills were crowded with students who had come to audit, drawn by the professor’s reputation.
Gao Wen was a True God in the field of computer architecture and low-level algorithms at Yan University, and an academician of the Huaxia Engineering Academy.
He rarely taught fundamental courses to undergraduates.
Today’s class, "Low-level Algorithms and High-Performance Computing Architecture," was actually the first lecture of the semester for freshmen. It was also one of the few professional introductory courses he would personally teach this term.
Because of this, not only had all the students from the School of Information Science shown up, but even top students from other schools had caught wind of it and rushed over, just for a chance to witness the True God in person.
Academician Gao stood at the lectern, chalk in hand, drawing a Logic diagram of a low-level system architecture on the blackboard.
"In a NUMA architecture, multi-core concurrency isn’t a simple superposition of threads."
"When two threads simultaneously modify different independent variables within the same cache line, it triggers a false sharing trap."
"At that point, the MESI cache coherence protocol will trigger a nanosecond-scale invalid data flush storm on the underlying physical bus, dragging the concurrent computing power you’re so proud of down to a crawl!"
Academician Gao spoke with eloquent ease from the lectern, while the freshmen below were completely baffled.
Although Academician Gao’s Logic was crystal clear, with each point connecting to the next, and they could follow the cause-and-effect relationships...
...they hadn’t encountered these specialized concepts of low-level hardware and cache coherence protocols yet. ’Is this really the kind of stuff that should be taught in an introductory course for freshmen?’
In fact, for someone at the level of an academician, standing at a lectern was never about teaching students a specific piece of knowledge.
What they imparted was a path, a brand-new way of thinking, a direction for breakthroughs that could shatter conventions!
As for teaching specific knowledge?
For example, how to write basic C++ syntax?
How to declare a variable?
How to call existing API interfaces?
Forget Academician Gao, an academician of the Huaxia Engineering Academy—not even a random professor pulled from Yan University’s School of Information Science would teach that!
Because in the eyes of these top scholars at Yan University, weren’t programming tools and language specifications—things you could look up like a dictionary—something that you, the best and brightest who got into Yan University, could learn on your own by pulling two all-nighters in your dorm?
Why would a university professor need to waste time teaching such basic stuff from a lectern?
This was the standard and character of Huaxia’s most prestigious university!
Although the students below were bewildered, they were still taking notes furiously, hoping to digest the information slowly back in their rooms.
Academician Gao paused and said sternly.
"Put your pens down. You don’t need to take notes."
"If you try to listen and write at the same time, you won’t be able to keep up with my pace."
As soon as he said this, the faces of the freshmen who had been furiously taking notes instantly turned red.
Just as they were feeling ashamed of their naive actions, Academician Gao suddenly chuckled.
"But you can record it with your phones. That thing can keep up..."
A wave of laughter erupted from the audience.
It was only then that this group of the nation’s brightest truly realized just how different university was from high school—both in terms of the subject matter and the professors.
Meanwhile, Li Dong, sitting in the very last row of the lecture hall, was growing more and more excited as he listened.
Others might not understand, but he could!
’So the cache coherence problem in multi-threaded concurrency is essentially a mapping of data contention at the physical level...’
RING RING RING.
The bell signaling the end of class rang.
Academician Gao stated directly.
"That’s all for today’s lecture. Class dismissed."
Li Dong shot up, grabbed his backpack, and prepared to rush down to the lectern to ask a question.
However, the habits he had formed back at Jiangcheng Seventh Middle School taught him a hard lesson.
He was sitting in the last row, and by the time he finally managed to run down to the side of the lectern...
...he was stunned.
’Seventh Middle School has failed me!’
Academician Gao was already surrounded by a crowd of enthusiastic top students.
"Teacher Gao, about the issue of cache line alignment..."
"Teacher Gao, how do you quantify the overhead of multi-threading locks in practical engineering..."
Li Dong could only stand helplessly on the outskirts of the crowd, waiting for the students in front of him to finish asking their questions.
Ten-plus minutes passed, and it was almost time for the next class to begin.
Academician Gao finally waved his hand at the students around him.
"Alright, everyone, you should go to your next class. For any remaining questions, you can ask your assigned professors."
Although everyone was quite disappointed, they couldn’t skip their next class, so they had no choice but to disperse.
Academician Gao walked out of the lecture hall.
Seeing this, Li Dong followed him.
In the hallway, Academician Gao noticed someone was following him and turned to look at Li Dong.
"Young man," Academician Gao asked with a smile.
"Don’t you have a class to get to?"
Li Dong replied.
"I’m not in this class."
Academician Gao paused for a moment, then it dawned on him.
"From Yuanpei?"
Li Dong nodded.
"Ha." Academician Gao burst out laughing.
He actually had courses listed with Yuanpei College, but it was rare to see a freshman who, right at the start of the semester, would skip his own college’s general education classes and run straight to the School of Information Science. Such students existed, but they were few and far between.
"Come on." Academician Gao beckoned, leading Li Dong across the skywalk of the Science Building to his private office in the School of Information Science.
Pushing the door open, Academician Gao sat down at his desk and gestured for Li Dong to sit as well, asking casually.
"So? Was there something in the lecture you didn’t understand?"
Li Dong shook his head.
"I understood everything. You explained it with profound insight yet in simple terms, analyzing the relationship between low-level hardware and software algorithms with exceptional clarity."
After hearing this, Academician Gao couldn’t help but smile.
’This student is quite interesting.’
’How much about low-level concurrency could a freshman possibly understand?’
’This kid is a smooth talker, very subtle about it. Pretty high EQ.’
Meanwhile, Li Dong, sitting across from him, had no idea that he had just spoken the honest truth, only to be mistaken for someone with high emotional intelligence.
"Then why did you follow me to my office? What did you want to ask?"
Academician Gao looked at him with great interest.
Li Dong got straight to the point.
"Teacher Gao, I’ve recently been researching low-level algorithm optimizations for calculating the non-trivial zeros of the Riemann Zeta function."
"I want to further optimize its memory allocation based on this multi-point evaluation, and try to push the computation scale to the trillion-level, or even to a higher, extremely High Tier range."
"But when I use FFT to perform a large-scale grid expansion of the Zeta function, I can never seem to get the low-level memory call Logic right."
"When the grid scale is magnified to the tens of millions or hundreds of millions, the computational redundancy is too great, often causing severe memory fragmentation or cache misses."
Li Dong explained some of the problems he had encountered while trying to embed concepts from Riemann’s Manuscript into a programming language.
"So, how can I refactor the low-level memory layout in C++ without changing the overall mathematical time complexity, in order to best accommodate the CPU’s cache prefetching mechanism?"
After hearing Li Dong’s words, Academician Gao put down his thermos.
He was particularly fond of students like this, who thought deeply for themselves.
He carefully considered the memory allocation Logic Li Dong had just described. Although he couldn’t completely grasp Li Dong’s dimensionality reduction algorithm from just a few questions...
...after all, his specialty wasn’t mathematics.
But he still identified some weaknesses in the framework’s hardware scheduling.
"Your way of thinking is very different from that of a normal student. Your approach is unconventional, but very interesting."
Academician Gao picked up a pen and drew a simple memory block diagram on a piece of paper.
"Since you’re using FFT for multi-point evaluation, you can’t think in terms of conventional contiguous memory allocation."
"Bit-reversal permutation will completely disrupt the spatial locality of the CPU cache."
"You have to manually perform blocking, splitting the massive grid matrix into small chunks that can fit completely into the L2 cache. Perform the computations within those small blocks before writing them back to main memory."
Academician Gao patiently explained the essence of memory alignment to Li Dong, every sentence packed with valuable information.
As Li Dong listened to Academician Gao, his [Code Intuition] instantly visualized these concepts.
"I understand now! Thank you, Teacher Gao!"
Li Dong was genuinely grateful. This was the benefit of having a great teacher. They might not have a cheat ability like Li Dong, but then again, neither did people like Newton, and that didn’t stop them from being incredible.
After asking his core academic question, Li Dong suddenly remembered a very practical problem.
His Lenovo laptop still wouldn’t turn on, and he hadn’t bought a new one yet.
So, he asked somewhat sheepishly.
"Um... Teacher Gao, can students apply to use the computer labs at our school?"
Academician Gao was sipping his tea and nearly choked when he heard the question.
"Our school’s computer labs are a public resource,"
Academician Gao explained, not knowing whether to laugh or cry.
"You can just swipe your campus card to get in and use them."
"Of course, if you need to run very large-scale computations, you can apply for nodes at the Supercomputing Center through the campus network using your student ID."
Only then did it dawn on Li Dong.
Academician Gao looked at the somewhat clueless young man before him and found him all the more interesting.
"Young man, what’s your name?" Academician Gao asked with a smile.
"My name is Li Dong."
"Li Dong..." Academician Gao nodded, committing the name to memory.