Choose One Main LLM Research Axis | Generated by AI
Question: Based on my current AI progress, how should I choose the next LLM research focus? Should I go broad (MoE, RL, KL, MLA, Flash Attention, etc.) or focus on one/two directions?
Answer:
Looking at your current trajectory, your friend is correct: the main risk is not lack of knowledge, but too many interesting directions without a research identity.
Your current profile is actually unusual:
- You already built software systems for 10+ years.
- You have trained GPT-style models yourself (nanoGPT, GPT-2 scale experiments).
- You have touched real GPUs (H200, MI300X, RTX 4070). (Zhiwei Li)
- You write and document aggressively. (Zhiwei Li)
- You prefer open source and source-code-level understanding.
So your advantage is not competing with PhD researchers doing pure theory. Your advantage is:
“I can read papers → modify code → run experiments → debug kernels/systems → publish engineering insights.”
I would choose a direction where this advantage compounds.
My recommendation: choose one main axis + one supporting axis
Main axis: Efficient LLM architecture + inference systems
Specifically:
MoE + MLA + Attention optimization + small-scale reproduction
Why?
Because this matches your hardware and engineering background.
DeepSeek-V2 is exactly this area: MoE + MLA. DeepSeek-V2-Lite has 16B total parameters but only 2.4B activated parameters, making it a good research target. (Hugging Face)
The questions are very engineering-heavy:
- How does routing work?
- How does expert imbalance happen?
- How does KV cache reduction work?
- Why does MLA reduce memory bandwidth?
- How do you implement efficient inference?
- How do you modify vLLM / kernels?
These are closer to your strengths.
A good 6-month identity:
“Open-source LLM efficiency researcher: reproducing and improving MoE/MLA inference.”
Second axis: RL / alignment, but not as primary
Your friend mentioned KL divergence and online policy distillation.
This is valuable, but I would not make it your main research.
Reason:
RLHF/RLVR requires:
- reward models
- large-scale experiments
- distributed training
- evaluation infrastructure
The barrier is higher.
Learn it enough:
- KL divergence
- PPO
- DPO
- GRPO
- rejection sampling
- online distillation
But use it as a tool.
Example:
“I improved MoE reasoning model efficiency using RL distillation.”
Better than:
“I study RL.”
Your current list ranked
Tier 1: Do deeply
1. MoE
★★★★★
Do:
- implement Switch Transformer MoE
- reproduce DeepSeekMoE idea
- train tiny MoE from scratch
Example:
GPT-2 124M
|
|
replace FFN
|
v
MoE GPT-2
8 experts
top-2 routing
load balancing loss
Measure:
- training speed
- activated params
- quality
- expert utilization
2. MLA
★★★★★
Very aligned.
Understand:
Normal attention:
K = X Wk
V = X Wv
KV cache:
[layer]
[token]
[key,value]
Problem:
Long context:
KV cache memory ↑↑↑
MLA:
KV
|
compress
|
latent vector
|
store smaller cache
DeepSeek’s MLA reduces KV cache pressure by compressing KV into latent space. (Hugging Face)
Implementation project:
Take nanoGPT:
replace:
CausalSelfAttention
with:
MultiHeadLatentAttention
Train.
That is a very strong portfolio project.
3. Flash Attention
★★★★☆
Learn.
But don’t spend 3 months here.
Understand:
Normal:
QK^T
|
softmax
|
PV
Problem:
materializes N×N attention matrix.
Flash:
Q block
K block
|
online softmax
|
V block
Focus:
- IO complexity
- SRAM/HBM
- CUDA/Triton implementation
Tier 2: Learn but don’t become identity
KL divergence
Learn mathematically:
KL(P||Q)
=
Σ P(x) log(P(x)/Q(x))
Why LLM cares:
Old model:
P_old
New model:
P_new
Prevent:
P_new drifting too far
Loss:
RL objective
reward
-
β KL(old,new)
Useful everywhere.
But KL itself is not a research direction.
Muon optimizer
Interesting but niche.
Learn after fundamentals.
What I would do if I were you
Next 3 months
Project 1
“nanoGPT-MoE”
Fork Karpathy nanoGPT.
Implement:
Dense FFN
|
v
MoE FFN
8 experts
top-k router
aux loss
Train:
GPT-2 50M
GPT-2 100M
Dataset:
FineWeb / TinyStories.
Write:
- architecture explanation
- training curves
- routing visualization
Project 2
“nanoGPT-MLA”
Implement:
Multi-head Attention
↓
Multi-head Latent Attention
Compare:
memory usage
speed
quality
KV cache
Project 3
Inference engineering
Modify:
- vLLM
- llama.cpp
- Triton kernels
Examples:
why MLA needs special kernel
why MoE routing costs latency
About companies
Your friend gave two paths:
Path A: company-driven
Examples:
Want DeepSeek-style companies:
Focus:
MoE
MLA
distributed training
CUDA/Triton
vLLM
Want OpenAI/Anthropic-style:
Focus:
reasoning
RL
post-training
eval
agents
Path B: frontier idea
Your idea:
simplify Transformer and attention
Actually interesting.
A possible research theme:
“Small efficient foundation models”
Examples:
Can a 1B model achieve 7B quality?
through:
MoE
better attention
distillation
RL
This matches your hardware constraints.
My suggested personal research statement for you
Not:
“I study LLM.”
Too broad.
Better:
“I build and optimize efficient open-source LLM architectures, focusing on MoE, latent attention, and inference efficiency.”
That connects:
- DeepSeek
- NVIDIA ecosystem
- open source
- your GPU experiments
- your coding background
Your next step should probably not be reading 100 papers.
Do:
- Read DeepSeek-V2 paper.
- Implement one component.
- Train a small model.
- Write results.
- Repeat.
You already have the “builder loop”; now narrow the research loop. (GitHub)
References:
- DeepSeek-V2: A Strong, Economical, and Efficient Mixture-of-Experts Language Model (GitHub)
- DeepSeek-V2-Lite model overview (Hugging Face)
- Hardware-Centric Analysis of DeepSeek’s Multi-Head Latent Attention (arXiv)