How does a mixture-of-experts transformer change cost and quality?
PICTURE THIS: A SENTENCE BECOMES TOKENS
The model does not read letters like humans. It reads these pieces, then predicts the next one.
Simple meaning
MoE routes each token to a few expert FFNs instead of one dense MLP.
WHY — Tokens instead of words?
LLMs use tokens (not full words) because it helps them:
question about Transformers.
trade-offs, and what you would actually do on a GenAI / LLM project - not buzzwords.
Each piece maps to a number the network can learn.
Fixed pieces are what transformers expect as input.
STEPS — What happens with tokens?
Before the model can read a sentence, it goes through these steps:
- 1MoE routes each token
to a few expert FFNs instead of one dense MLP.
- 2Sparse activation raises parameter
count without a matching FLOP increase per token.
- 3Load balancing, expert parallelism,
and noisy routing are the operational risks.
- 4Context mix
Attention looks at nearby tokens together.
- 5Next token
The model scores what should come next.
- 6Decode
IDs turn back into readable text.
EXAMPLE — See it in action
Let's see how a real sentence is tokenized (tokens may vary by model):
Note: Actual tokens and IDs depend on the tokenizer (e.g., GPT, Llama, etc.).
Key takeaway
MoE routes each token to a few expert FFNs instead of one dense MLP. Sparse activation raises parameter count without a matching FLOP increase per token.