Estimate Complexity
Tests an AI's ability to make educated estimates based on technical knowledge
The Prompt
Estimate the total number of FLOPs required to train GPT-3 without searching online. Explain your reasoning step by step.
Model Responses
To estimate the total number of FLOPs required to train GPT-3, let's break it down into key components.
1. Model Size and Parameters
GPT-3 has 175 billion parameters.
2. FLOPs per Forward and Backward Pass
In deep learning, the FLOPs required for a forward pass and backward pass are estimated as:
- Forward pass: ( 2 imes ) the number of parameters
- Backward pass: ( 2 imes ) the FLOPs of the forward pass
Thus, total FLOPs per training step:
[ ext{Total FLOPs per step} = 6 imes ext{number of parameters} imes ext{tokens per batch} ]
For GPT-3, let's assume 175B parameters and a batch size of 2048 tokens (common for large-scale training).
[ ext{FLOPs per training step} = 6 imes 175 imes 10^9 imes 2048 ]
[ = 2.15 imes 10^{15} ext{ FLOPs per step} ]
3. Total Training Steps
GPT-3 was trained with 300 billion tokens (as per OpenAI's paper).
If the batch size is 2048 tokens, the total number of steps is:
[ ext{Total steps} = rac{300 imes 10^9}{2048} approx 1.46 imes 10^8 ]
4. Total FLOPs Required
Multiplying the FLOPs per step by the total number of steps:
[ ext{Total FLOPs} = (2.15 imes 10^{15}) imes (1.46 imes 10^8) ]
[ approx 3.14 imes 10^{23} ext{ FLOPs} ]
Final Answer:
The estimated total number of FLOPs required to train GPT-3 is about ( 3.14 imes 10^{23} ) floating point operations.
I'll help you estimate the FLOPs (Floating Point Operations) required to train GPT-3 from first principles. Let's break this down step by step.
- Model Architecture Parameters
- GPT-3 has 175 billion parameters
- Uses transformer architecture with attention mechanism
- Training involves forward pass, backward pass, and optimizer updates
- Key Components per Token For each token in the sequence, we need to calculate:
a) Self-Attention
- Query, Key, Value projections: 3 × (n_emb × n_emb)
- Attention scores: n_seq × n_seq × n_emb
- Attention output: n_seq × n_emb × n_emb
- For h=96 attention heads
b) Feed-Forward Network (FFN)
- Two linear transformations
- First projection: n_emb × (4 × n_emb)
- Second projection: (4 × n_emb) × n_emb
- GELU activations
- Training Details
- Context length: 2048 tokens
- Batch size: ~1.5M tokens per batch (approximate)
- Training tokens: ~300B tokens
- FLOPs Calculation
Let's calculate for one forward pass through a single token:
a) Self-Attention FLOPs
- QKV projections: 3 × (12288 × 12288) = ~450M FLOPs
- Attention scores: 2048 × 2048 × 12288 = ~50B FLOPs
- Attention output: 2048 × 12288 × 12288 = ~300B FLOPs
- Multiply by 96 heads: ~35T FLOPs
b) FFN FLOPs
- First projection: 12288 × 49152 = ~600M FLOPs
- Second projection: 49152 × 12288 = ~600M FLOPs
- Total FFN: ~1.2B FLOPs
c) Per Token Total
- Forward pass: ~36T FLOPs
- Backward pass (roughly 2x forward): ~72T FLOPs
- Parameter updates (1x forward): ~36T FLOPs
- Total per token: ~144T FLOPs
- Total Training FLOPs
- Number of tokens: 300B
- FLOPs per token: 144T
- Total FLOPs: 300B × 144T = ~43,200 Zettaflops (4.32 × 10^22 FLOPs)
This is a rough estimate that considers:
- Main computational bottlenecks
- Both forward and backward passes
- Parameter updates
- Major attention and FFN operations
The actual number might be higher due to:
- Additional layer normalizations
- Activation functions
- Memory access operations
- Optimizer-specific computations (Adam)
- Various other overhead operations
This estimate aligns with the general understanding that training large language models requires enormous computational resources, in the order of zettaflops of compute.
Note: This is an approximation based on the model's known architecture and typical training procedures. The actual number could vary based on specific implementation details, optimizations, and hardware-specific considerations.
Estimating FLOPs for GPT-3 Training
I'll estimate the total number of FLOPs (Floating Point Operations) required to train GPT-3 by breaking this down step by step.
GPT-3 Architecture Facts
From what I recall about GPT-3:
- Parameters: ~175 billion parameters
- Training tokens: ~300-400 billion tokens
- Architecture: Transformer decoder-only
- Context length: 2048 tokens
Step 1: FLOPs per Forward Pass
In a transformer model, the main computational components are:
- Self-attention: O(s²d) where s is sequence length and d is model dimension
- Feed-forward networks: O(sd²)
For GPT-3, if we assume:
- Sequence length (s) = 2048
- Model dimension (d) ≈ 12288 (estimated based on parameter count)
- Number of layers ≈ 96 (estimated)
FLOPs per token in forward pass:
- Self-attention: ~2 × 2048² × 12288 × 96 ≈ 4.8 × 10¹²
- Feed-forward: ~2 × 2048 × 12288² × 96 ≈ 5.9 × 10¹³
- Total per forward pass: ~6.4 × 10¹³ FLOPs
Step 2: FLOPs per Backward Pass
The backward pass typically requires about 2× the computation of the forward pass:
- Backward pass: ~2 × 6.4 × 10¹³ ≈ 1.3 × 10¹⁴ FLOPs
Step 3: FLOPs per Training Step
For each training step:
- Forward + backward: ~6.4 × 10¹³ + 1.3 × 10¹⁴ ≈ 1.9 × 10¹⁴ FLOPs
Step 4: Total Training FLOPs
If GPT-3 was trained on ~300 billion tokens:
- Total FLOPs: 1.9 × 10¹⁴ × 3 × 10¹¹ ≈ 5.7 × 10²⁵ FLOPs
Accounting for optimization overhead, gradient accumulation, and other factors, we might round up to:
- Total training FLOPs: ~10²⁶ FLOPs
This is in the same order of magnitude as other estimates I've seen, which typically place GPT-3 training at around 3-6 × 10²³ FLOPs. My estimate is a bit higher, which could be due to overestimating some of the architectural parameters or not accounting for optimizations like mixed precision training.
Estimating GPT-3 Training FLOPs
I'll estimate the total number of floating point operations (FLOPs) required to train GPT-3 by breaking down the calculation step by step.
Model Architecture Facts
- GPT-3 has approximately 175 billion parameters
- Uses a transformer architecture with multiple layers
- Context length of 2048 tokens
- Trained on approximately 300 billion tokens
Calculating FLOPs per Token
For transformer models, we need to account for operations in:
- Self-attention mechanisms
- Feed-forward networks
- Layer normalization and other operations
For GPT-3, let's use these parameters:
- Embedding dimension (d): ~12,288
- Number of layers (L): ~96
- Context length (s): 2,048
Forward Pass Calculation
For each token in each layer:
- Self-attention: ~4 × d² + 2 × d × s FLOPs
- Feed-forward network: ~8 × d² FLOPs
- Other operations: ~d FLOPs
Total FLOPs per token (forward pass): ≈ L × (12 × d² + 2 × d × s) ≈ 96 × (12 × 12,288² + 2 × 12,288 × 2,048) ≈ 96 × (1.8 × 10⁹ + 5 × 10⁷) ≈ 1.8 × 10¹¹ FLOPs
Backward Pass
The backward pass typically requires about 2× the computation of the forward pass: ≈ 2 × 1.8 × 10¹¹ ≈ 3.6 × 10¹¹ FLOPs
Total FLOPs per token (forward + backward): ≈ 1.8 × 10¹¹ + 3.6 × 10¹¹ ≈ 5.4 × 10¹¹ FLOPs
Total Training FLOPs
Multiply by the total number of tokens processed: ≈ 5.4 × 10¹¹ × 300 × 10⁹ ≈ 1.62 × 10²³ FLOPs
Alternative Calculation
As a sanity check, using a simpler heuristic:
- Each parameter requires ~2-4 FLOPs per token (including forward, backward, and weight update)
- 175B parameters × 4 FLOPs × 300B tokens ≈ 2.1 × 10²³ FLOPs
Conclusion
The total training computation for GPT-3 was approximately 1.6-2.1 × 10²³ FLOPs (160-210 zettaFLOPs).
This massive computational requirement explains why training such models costs millions of dollars and requires specialized supercomputing infrastructure.
To estimate the total number of FLOPs required to train GPT-3, we use the following reasoning:
-
Model Parameters (P):
GPT-3 has 175 billion parameters ((P = 175 imes 10^9)). -
Training Tokens (N):
GPT-3 was trained on approximately 300 billion tokens ((N = 300 imes 10^9)). -
FLOPs per Token:
- A forward pass requires ~(2P) FLOPs per token (each parameter involves a multiply-accumulate operation, which counts as 2 FLOPs).
- A backward pass (for gradients) is roughly twice as expensive as the forward pass, requiring ~(4P) FLOPs per token.
- Total FLOPs per token: (2P + 4P = 6P).
-
Total Training FLOPs:
Multiply FLOPs per token by the total number of tokens:
[ ext{FLOPs} = 6 imes P imes N = 6 imes 175 imes 10^9 imes 300 imes 10^9 = 3.15 imes 10^{23} , ext{FLOPs}. ]
Final Answer:
The total number of FLOPs required to train GPT-3 is approximately (3.1 imes 10^{23}) FLOPs.
Okay, let's break down this estimation step-by-step, making some reasonable assumptions along the way, since we can't look up the exact details. We'll be aiming for a rough order-of-magnitude estimate, not a precise figure.
1. Key Parameters & Assumptions (and why we need them):
To estimate FLOPs, we need to consider several factors influencing computational cost:
- Model Size (Parameters): This is the most crucial factor. GPT-3 is famously large. Let's assume it has 175 billion parameters (this is the generally cited number, and we're working without looking things up). Crucially, each parameter is not a single FLOP. Each parameter participates in many FLOPs during both forward and backward passes.
- Training Data Size (Tokens): GPT-3 was trained on a massive dataset. We need a rough estimate of the number of tokens in the training data. Let's assume it was trained on roughly 300 billion tokens. This is based on the common crawl dataset being cited, and estimates for the number of tokens are in this region.
- Training Epochs: How many times did the model see the entire training dataset? Large language models are typically trained for a relatively small number of epochs, sometimes even less than one full epoch (i.e., they don't see every token). Let's assume an effective number of epochs of 0.5, which takes into account how the model likely saw the data.
- Sequence Length: The context window the model processes at a time. A longer sequence length increases computational cost. Let's assume an average sequence length of 2048 tokens during training (This is a typical size for these models).
- Batch Size: How many sequences are processed in parallel. Larger batch sizes generally mean more efficient use of hardware, but there are practical limits. We don't have enough information on this to factor it directly, so we will use the rule of thumb in step 2.
- Forward Pass vs. Backward Pass: Backpropagation (used for calculating gradients and updating weights) is computationally more expensive than the forward pass. A common rule of thumb is that the backward pass takes roughly twice the computation of the forward pass.
2. The "6N" Rule of Thumb (and why it's useful):
A widely used (and relatively accurate) approximation for the FLOPs required to train a transformer model is:
FLOPs ≈ 6 * Number of Parameters * Number of Tokens
-
Why 6? This factor accounts for several things:
- Forward Pass (2): Consider the matrix multiplications involved in a transformer. For each token in a sequence, you're essentially doing a matrix multiplication (embedding size * number of parameters). This gives us a factor of roughly 2 (simplified).
- Backward Pass (4): The backward pass involves calculating gradients, which roughly doubles the computation of the forward pass, so 2 * 2 = 4.
- Total (6): 2 (forward) + 4 (backward) = 6
-
Why this is useful: This rule of thumb avoids having to delve into the specifics of the transformer architecture (number of layers, attention heads, etc.). It captures the dominant computational cost, which is the interaction of every parameter with every token.
3. Calculation:
Let's plug in our estimates:
- Number of Parameters (N) = 175 billion = 1.75 x 10^11
- Number of Tokens = 300 billion = 3 x 10^11
- Number of Epochs = 0.5
Total number of tokens seen: 3 x 10^11 * 0.5 = 1.5 x 10^11
FLOPs ≈ 6 * (1.75 x 10^11) * (1.5 x 10^11) FLOPs ≈ 6 * 2.625 * 10^22 FLOPs ≈ 15.75 x 10^22 FLOPs ≈ 1.575 x 10^23
4. Final Answer and Considerations:
Our estimated total number of FLOPs required to train GPT-3 is approximately 1.6 x 10^23 FLOPs. This is 16 zettaFLOPs.
- Order of Magnitude: This is the most important takeaway. We're in the ballpark of 10^23. The precise number could be somewhat higher or lower, but this gives us a good sense of the scale.
- Simplifications: We've made many simplifying assumptions. We didn't explicitly account for:
- Optimizer FLOPs (e.g., Adam optimizer updates).
- Specific architecture details (number of layers, attention heads, feedforward network dimensions).
- Data loading and preprocessing overhead.
- The "effective" number of epochs is a very rough estimate.
- Variations in sequence length during training.
- The 6N rule of thumb The rule is not perfect, but the main limiting factor is likely the number of tokens.
In conclusion, our reasoned estimate places the FLOPs required for training GPT-3 in the range of zettaFLOPs, highlighting the immense computational resources needed for such a large language model. This demonstrates that the number of parameters and the number of tokens are crucial.
Estimating the total FLOPs for training GPT-3 without searching online requires making some educated assumptions and using scaling laws and general knowledge about large language models. Here's a step-by-step reasoning process:
1. Understanding the Core Components of FLOPs Calculation in Transformer Training:
- Model Size (Number of Parameters): The number of parameters in GPT-3 is the most crucial factor. We know it's approximately 175 billion parameters. This is a widely reported figure and a good starting point. Larger models inherently require more computations.
- Dataset Size (Number of Tokens): GPT-3 was trained on a massive dataset. While the exact size isn't publicly memorized to a precise number, it's known to be in the trillions of tokens. Let's assume a dataset size in the order of 300 billion to 1 trillion words initially for estimation, which translates to roughly 400 billion to 1.3 trillion tokens (assuming approximately 1.3 tokens per word on average in English text). We'll use a mid-range estimate for now.
- Number of Training Epochs/Passes: Large language models are typically not trained for a full epoch (one complete pass through the entire dataset). They are trained for a fraction of an epoch. Let's assume GPT-3 was trained for roughly 0.5 to 1 effective epochs or passes over the dataset. "Effective epoch" means the data is sampled in a way that is roughly equivalent to passing through the dataset a fraction of a time.
- FLOPs per Parameter per Token: For a Transformer model, a simplified approximation for the FLOPs per parameter per token in a single forward and backward pass is often considered to be around 6 FLOPs. This '6' is a rough estimate that accounts for matrix multiplications and other operations in the attention and feedforward layers during both forward and backward propagation. It's a simplification, but useful for estimation.
2. Calculating FLOPs per Token:
Using the approximation of 6 FLOPs per parameter per token and the model size:
- FLOPs per token per pass ≈ 6 * (Number of Parameters)
- FLOPs per token per pass ≈ 6 * (175 * 10<sup>9</sup>)
- FLOPs per token per pass ≈ 1050 * 10<sup>9</sup>
- FLOPs per token per pass ≈ 1.05 * 10<sup>12</sup> FLOPs per token per pass (approximately 1 TeraFLOP per token per pass).
3. Estimating Total Tokens Processed:
Let's take a mid-range estimate for the dataset size in tokens. If we assume around 500 billion words in the training dataset, and roughly 1.3 tokens per word, we get:
- Estimated tokens ≈ 500 * 10<sup>9</sup> words * 1.3 tokens/word
- Estimated tokens ≈ 650 * 10<sup>9</sup> tokens
- Estimated tokens ≈ 650 billion tokens
Let's also consider a slightly larger estimate as GPT-3's dataset was massive, perhaps closer to 1 trillion tokens as an upper bound for this estimation range.
4. Estimating Total Training FLOPs:
Now we can combine the FLOPs per token, estimated tokens, and the number of passes:
- Total FLOPs ≈ (FLOPs per token per pass) * (Total Tokens) * (Number of Passes)
Let's calculate a lower and upper bound estimate based on our assumptions:
-
Lower Bound Estimate (using 650 billion tokens and 0.5 passes):
- Total FLOPs ≈ (1.05 * 10<sup>12</sup> FLOPs/token) * (650 * 10<sup>9</sup> tokens) * (0.5 passes)
- Total FLOPs ≈ (1.05 * 650 * 0.5) * 10<sup>(12+9)</sup>
- Total FLOPs ≈ 341.25 * 10<sup>21</sup>
- Total FLOPs ≈ 3.4 * 10<sup>23</sup> FLOPs
-
Upper Bound Estimate (using 1 trillion tokens and 1 pass):
- Total FLOPs ≈ (1.05 * 10<sup>12</sup> FLOPs/token) * (1 * 10<sup>12</sup> tokens) * (1 pass)
- Total FLOPs ≈ 1.05 * 10<sup>(12+12)</sup>
- Total FLOPs ≈ 1.05 * 10<sup>24</sup> FLOPs
5. Reasoning and Interpretation:
- Model Size Dominance: The 175 billion parameters are the primary driver of the high FLOPs count. Every token processed involves computations proportional to this massive parameter count.
- Dataset Size Influence: The trillions of tokens ensure the model sees a vast amount of data, but the number of passes is less than a full epoch for efficiency and generalization. A larger dataset naturally leads to more FLOPs.
- Simplified FLOPs per Token: The '6 FLOPs per parameter per token' is a significant simplification. The actual number can vary depending on the specific Transformer architecture, optimizations, and hardware. However, it provides a reasonable order-of-magnitude estimate.
- Epochs and Data Usage: Training for less than a full epoch is common in large models. This is a trade-off between compute cost and model performance. It's likely GPT-3 was trained with sophisticated data sampling and potentially multiple passes over parts of the dataset, but less than a full epoch in terms of unique data exposure.
- Order of Magnitude Estimate: These calculations are intended to provide an estimate of the order of magnitude. The actual FLOPs can vary based on implementation details, optimizations, and hardware used. However, the range of 3 * 10<sup>23</sup> to 1 * 10<sup>24</sup> FLOPs is a reasonable estimate based on general principles.
Conclusion:
Based on these estimations, the total number of FLOPs required to train GPT-3 is likely in the range of 3 * 10<sup>23</sup> to 1 * 10<sup>24</sup> FLOPs. A reasonable single point estimate within this range would be around ~3 * 10<sup>23</sup> FLOPs to ~1 * 10<sup>24</sup> FLOPs.
In summary, the estimated total FLOPs for training GPT-3 is in the order of hundreds of zettaFLOPs (10<sup>21</sup> FLOPs) to a few exaFLOPs (10<sup>18</sup> FLOPs) per second for a certain duration, ultimately resulting in a total computation in the range of 10<sup>23</sup> to 10<sup>24</sup> FLOPs. This is a massive amount of computation, highlighting the scale of resources needed to train state-of-the-art large language models.
Important Note: This is an estimation without searching online. Actual numbers might be slightly different, but the order of magnitude should be in the ballpark. Precise details would require access to internal training logs and architecture specifics which are not publicly available.
Below is one way to arrive at a back-of-the-envelope estimate for the total floating-point operations (FLOPs) needed to train GPT-3 (the 175B-parameter model). Note that different sources use slightly different assumptions, so you may see figures that differ by factors of 2–3; however, the overall scale (10^23 FLOPs) remains consistent.
1. Key Quantities
- Number of parameters (Nₚ): 175 billion (1.75 × 10^11)
- Number of training tokens (Nₜ): ~300 billion (3.0 × 10^11)
- Rule-of-thumb for FLOPs per parameter per token: A common rough estimate is 6 FLOPs per parameter per token for a full forward-and-backward pass with Adam-style updates.
Why 6?
- Forward pass often taken as ~2 × Nₚ FLOPs.
- Backward pass can be roughly twice the cost of the forward pass (~4 × Nₚ).
- Together → 2 + 4 = 6 × Nₚ FLOPs per token.
(Exact counts differ depending on the details of the architecture, hardware efficiency, and whether you count a multiply-add as one or two FLOPs, but 6 is a convenient ballpark multiplier.)
2. Core Calculation
Using the 6 FLOPs rule of thumb:
[ ext{Total FLOPs} ;approx; 6 ; imes; N_p ; imes; N_t. ]
Plug in the numbers:
- (N_p = 1.75 imes 10^{11}) (175B parameters).
- (N_t = 3.0 imes 10^{11}) (300B tokens).
- Multiplier = 6.
So,
[ ext{Total FLOPs} ;=; 6 ; imes; (1.75 imes 10^{11}) ; imes; (3.0 imes 10^{11}). ]
First, multiply the “nice” numbers:
- (6 imes 1.75 = 10.5)
- (10.5 imes 3.0 = 31.5)
So the coefficient is 31.5. Now include the powers of ten:
- (31.5 imes 10^{11} imes 10^{11} = 31.5 imes 10^{22} = 3.15 imes 10^{23}.)
Hence,
[ ext{Total FLOPs} ;approx; 3.15 imes 10^{23}. ]
3. Result and Interpretation
Therefore, a rough estimate for the total training cost of GPT-3 (175B) is on the order of
[
mathbf{3 imes 10^{23}} ext{ FLOPs.}
]
Depending on exact architectural details, optimizer choices, hardware efficiency, and definitions of FLOPs vs. MACs (multiply-accumulate operations), public estimates generally range from around (2 imes 10^{23}) to (4 imes 10^{23}). But the important takeaway is that it is a few times (10^{23}) FLOPs.
4. Summary
- Identify parameters and tokens: 175B parameters, 300B tokens.
- Adopt the “6 FLOPs per parameter per token” rule for forward + backward + update.
- Multiply: (6 imes 1.75 imes 10^{11} imes 3.0 imes 10^{11} approx 3.15 imes 10^{23}).
This simple calculation gives a ballpark figure without delving into the fine details of the GPT-3 architecture or specifics of training hardware.
Below is a step‐by‐step estimation:
-
Parameters Count:
GPT‑3 has about 175 billion parameters, i.e. roughly 1.75×10¹¹ parameters. -
Training Data:
The model was trained on a large corpus that can be estimated at around 300 billion tokens (≈3×10¹¹ tokens). -
FLOPs per Token:
In training deep networks like GPT‑3, the forward pass involves roughly one multiply–accumulate per parameter per token, but the backward pass (for computing gradients) costs about 2–3 times as much as the forward pass. A common rule‐of‐thumb is that training requires roughly 6 times as many FLOPs as a single forward pass. -
Total FLOPs Calculation:
The total number of FLOPs is therefore approximately:
[ ext{FLOPs} approx 6 imes ( ext{number of parameters}) imes ( ext{number of tokens}) ] Plugging in the numbers: [ ext{FLOPs} approx 6 imes 1.75 imes 10^{11} imes 3 imes 10^{11} approx 6 imes 5.25 imes 10^{22} approx 3.15 imes 10^{23} ] -
Final Estimate:
So, the training of GPT‑3 likely required on the order of 3×10²³ FLOPs.
This is an approximate calculation that combines rough estimates for both the number of training tokens and the factor accounting for both the forward and backward passes. Variations in these estimates or the exact training setup could change the final number by a factor of a few, but 3×10²³ FLOPs is a commonly cited ballpark figure.
To estimate the total number of FLOPs (Floating Point Operations) required to train GPT-3, we’ll need to make some reasonable assumptions based on what’s generally known about large language models like GPT-3, its architecture, and typical training procedures. GPT-3, developed by OpenAI, is a massive model with 175 billion parameters, and while exact training details aren’t fully public, we can piece together an estimate using standard practices in machine learning.
Step 1: Understand the Key Components
The number of FLOPs to train a model depends on:
- Number of parameters (P): GPT-3 has 175 billion parameters.
- Training dataset size (D): The number of tokens the model is trained on.
- Number of training steps (S): How many times the model processes the data (related to epochs and batch size).
- FLOPs per parameter update: How many operations are performed per parameter per token.
Step 2: Estimate FLOPs per Forward and Backward Pass
For transformer models like GPT-3, training involves both a forward pass (computing predictions) and a backward pass (computing gradients). A common heuristic in the field is that:
- A single forward pass through a dense neural network layer requires about 2 FLOPs per parameter per token (multiply and add for each weight).
- The backward pass typically takes about twice as many FLOPs as the forward pass due to gradient computations, so roughly 4 FLOPs per parameter per token.
- Total: ~6 FLOPs per parameter per token for one full training step (forward + backward).
For GPT-3 with 175 billion parameters, processing one token requires: [ 6 imes 175 imes 10^9 = 1.05 imes 10^{12} ext{ FLOPs per token} ]
Step 3: Estimate the Training Dataset Size
GPT-3 was reportedly trained on a massive corpus, often cited as hundreds of billions of tokens. Let’s assume 300 billion tokens, a plausible figure based on discussions about large language model datasets (e.g., Common Crawl, books, and other sources). This is the total number of tokens processed during training, factoring in how data is sampled over epochs.
Step 4: Calculate Total FLOPs for One Pass
If the model processes 300 billion tokens once, the total FLOPs would be: [ 1.05 imes 10^{12} ext{ FLOPs/token} imes 300 imes 10^9 ext{ tokens} = 3.15 imes 10^{23} ext{ FLOPs} ] This assumes one full pass through the dataset, but training typically involves multiple passes or iterations over the data, adjusted by batch size and optimization.
Step 5: Adjust for Training Dynamics
Training isn’t a single pass—it involves multiple updates to converge. The number of training steps depends on:
- Batch size (B): GPT-3 likely used a large batch size (e.g., 3.2 million tokens, as seen in some large-scale models).
- Total tokens processed: For optimization, models process tokens multiple times. A rule of thumb is that total tokens processed ≈ 2–3× the dataset size, accounting for multiple epochs or sampling.
Let’s assume the model effectively processes 900 billion tokens (3× the dataset size) over training. Then: [ 1.05 imes 10^{12} ext{ FLOPs/token} imes 900 imes 10^9 ext{ tokens} = 9.45 imes 10^{23} ext{ FLOPs} ]
Step 6: Account for Model Architecture Specifics
GPT-3 is a sparse transformer in some variants (e.g., earlier GPT models used sparsity), but the 175B version is dense. The 6 FLOPs/parameter/token heuristic holds for dense models. We’re not factoring in optimizations like mixed-precision training (FP16), which reduces compute slightly but doesn’t change the order of magnitude significantly.
Step 7: Final Estimate
Based on this reasoning, the total FLOPs to train GPT-3 is approximately: [ 9.45 imes 10^{23} ext{ FLOPs} ] or roughly ( 10^{24} ) FLOPs when rounded for simplicity.
Reasoning Check
- Comparison to known models: Smaller models like BERT (110M parameters, ~10B tokens) require ~10^19 FLOPs. Scaling to GPT-3’s size (175B parameters, ~900B tokens) suggests a 10,000× increase, aligning with ~10^23–10^24 FLOPs.
- Hardware context: Training GPT-3 took months on thousands of GPUs. A V100 GPU performs ~10^14 FLOPs/second; 10^24 FLOPs over 3 months (~10^7 seconds) with 10,000 GPUs is plausible.
Conclusion
The total FLOPs required to train GPT-3 is estimated at approximately ( 10^{24} ) FLOPs. This is a rough estimate, but it aligns with the scale of compute expected for a model of this size and training complexity.
To estimate the total number of Floating Point Operations (FLOPs) required to train GPT-3 without searching online, I’ll proceed step by step, relying on general knowledge about the model and standard methods for estimating training compute in large language models. Here’s my reasoning:
Step 1: Understand GPT-3’s Scale
GPT-3, developed by OpenAI, is a large-scale transformer-based language model known for its impressive natural language processing capabilities. A key piece of information is its size, measured by the number of parameters. Based on what I recall, GPT-3 has approximately 175 billion parameters. This number, denoted as ( N = 175 imes 10^9 = 1.75 imes 10^{11} ), will be central to our computation.
Step 2: Identify the Training Dataset Size
The number of FLOPs depends not only on the model’s parameters but also on the amount of data it processes during training. GPT-3 was trained on a massive dataset, including sources like filtered Common Crawl, Wikipedia, books, and other web texts. I estimate that the total number of tokens in the training dataset is around 300 billion, a figure that aligns with typical reports for models of this scale. So, let’s define ( T = 300 imes 10^9 = 3 imes 10^{11} ) as the total number of training tokens. For large language models like GPT-3, training typically involves a single pass (one epoch) over the dataset, so ( T ) represents the total tokens processed.
Step 3: Recall the FLOPs Estimation Formula
To estimate the FLOPs required for training, I need a method that ties the model size (( N )) and training data size (( T )) to computational effort. In deep learning, particularly for transformer models, a common approximation for total training FLOPs is:
[ C = 6 imes N imes T ]
Here, ( C ) is the total compute in FLOPs, ( N ) is the number of parameters, and ( T ) is the number of tokens. The factor of 6 arises from the computational cost per token during training, which includes:
- Forward pass: Approximately 2 FLOPs per parameter per token (one multiplication and one addition in matrix operations).
- Backward pass: Roughly 4 FLOPs per parameter per token (gradient computations typically double or triple the forward pass cost due to chain rule calculations).
Together, this suggests about 6 FLOPs per parameter per token, accounting for both forward and backward passes in a single training step. This approximation is widely used in analyses of large language models and simplifies the complex operations (e.g., attention mechanisms, feed-forward layers) into a single constant factor.
Step 4: Compute the Total FLOPs
Using the formula ( C = 6 imes N imes T ), I’ll plug in the values:
- ( N = 1.75 imes 10^{11} ) (parameters)
- ( T = 3 imes 10^{11} ) (tokens)
First, calculate the product of ( N ) and ( T ):
[ N imes T = (1.75 imes 10^{11}) imes (3 imes 10^{11}) ]
- Coefficients: ( 1.75 imes 3 = 5.25 )
- Exponents: ( 10^{11} imes 10^{11} = 10^{11+11} = 10^{22} )
So:
[ N imes T = 5.25 imes 10^{22} ]
Now, multiply by 6:
[ C = 6 imes 5.25 imes 10^{22} ]
- ( 6 imes 5.25 = 31.5 )
- ( 31.5 imes 10^{22} = 3.15 imes 10^{23} )
Thus, the total estimated FLOPs is:
[ C = 3.15 imes 10^{23} ext{ FLOPs} ]
Step 5: Validate the Estimate
To ensure this makes sense, consider the scale. Large language models like GPT-3 require immense computational resources, often measured in petaFLOP-days (1 petaFLOP = ( 10^{15} ) FLOPs). Converting our estimate:
- ( 3.15 imes 10^{23} div 10^{15} = 3.15 imes 10^8 ) petaFLOPs
- If training took 10 days on hardware delivering ( 3.15 imes 10^7 ) petaFLOPs per day, that’s plausible for a supercomputing cluster (e.g., thousands of GPUs or TPUs).
This magnitude aligns with the computational feats reported for models like GPT-3, though exact hardware details aren’t needed for this rough estimate.
Step 6: Address Potential Adjustments
The formula assumes a simplified transformer architecture and one epoch of training. Factors like multiple epochs, optimizer overhead (e.g., Adam), or specific architectural details (e.g., GPT-3 has 96 layers) could adjust the constant factor slightly. However, ( 6 imes N imes T ) is a standard heuristic in scaling law studies and suffices for an order-of-magnitude estimate without precise architectural data.
Final Answer
Based on this reasoning, the total number of FLOPs required to train GPT-3, with 175 billion parameters and 300 billion training tokens, is approximately 3.15 × 10²³ FLOPs. This estimate leverages a widely accepted approximation, balancing simplicity with the scale of modern language model training.
Let's estimate the total number of floating-point operations (FLOPs) required to train GPT-3 step by step, using reasonable assumptions and approximations:
Step 1: Identify GPT-3 Parameters and Training Setup
- GPT-3 has approximately (175 ext{ billion}) parameters.
- Typically, GPT-3 is trained using transformer architecture, which primarily consists of attention layers and feed-forward layers.
- Let's assume GPT-3 is trained with a context length (sequence length) of approximately (2048) tokens per training example.
- Assume GPT-3 was trained for approximately (300 ext{ billion tokens}) (a common estimate).
Step 2: Estimate FLOPs per Token
The transformer architecture primarily consists of two main components per layer:
- Self-attention layers: complexity (O(n^2 cdot d))
- Feed-forward layers: complexity (O(n cdot d^2))
Where:
- (n) is the sequence length (context length)
- (d) is the hidden dimension size of the model
GPT-3 (175B) typically has:
- Hidden dimension (d approx 12288) (common for GPT-3)
- Number of layers (L approx 96) (common for GPT-3)
Let's verify quickly:
- Parameters in transformer ≈ (2 imes d^2 imes L) (approximation, ignoring embedding layers and biases)
- Check: (2 imes 12288^2 imes 96 approx 2 imes 1.51 imes 10^8 imes 96 approx 2.9 imes 10^{10}) parameters. This is about 29 billion parameters. GPT-3 has 175 billion parameters, meaning the actual GPT-3 has more complexity (due to embedding layers, attention heads, biases, and output layers). Indeed, GPT-3 has multiple attention heads and embedding layers, so let's trust the known parameter count (175B) and proceed with a simplified calculation.
Step 3: Simplified FLOPs per Token Estimation
A common simplified rule-of-thumb for transformer models is that training one token requires approximately (6 imes) the number of parameters in FLOPs (forward + backward pass combined). This heuristic is widely used in practice.
Thus, for GPT-3 (175B parameters):
- FLOPs per token ≈ (6 imes 175 imes 10^9 = 1.05 imes 10^{12}) FLOPs per token.
Step 4: Total FLOPs for Training
Given GPT-3 was trained on approximately (300 ext{ billion tokens}):
[ ext{Total FLOPs} = ( ext{FLOPs per token}) imes ( ext{number of tokens}) ]
[ = (1.05 imes 10^{12}) imes (3.0 imes 10^{11}) ]
[ = 3.15 imes 10^{23} ext{ FLOPs} ]
Step 5: Final Approximation
Thus, the total number of FLOPs required to train GPT-3 is approximately:
[ oxed{3.15 imes 10^{23} ext{ FLOPs}} ]
Summary of Reasoning:
- GPT-3 parameters: (175 ext{ billion})
- FLOPs per token (heuristic): (6 imes ext{parameters})
- Total tokens trained: (300 ext{ billion})
- Total FLOPs ≈ (3.15 imes 10^{23})
This is a rough but reasonable estimate based on common heuristics and known GPT-3 parameters.