GPU Memory Calculator 🧮
GPU Memory needs scale up based on the size of the model. To quickly calculate the memory required for a model you can use the calculators below.
For inference memory required is typically 2 x the number of parameters, this is because each parameter is typically two bytes (FP16). So a 7B parameter model takes 14GB.
For training in mixed precision (FP16) it’s typically 18x the number of parameters plus activations, this is typically 22-32x the number of parameters. So for a 7 B parameter model, you’ll need at least 224GB of GPU memory.
These instance types have the following GPU memory:
Instance | GPU | GPU Memory |
---|---|---|
g5 | A10G | 24 GB |
p4d | A100 | 40 GB |
p4de | A100 | 80 GB |
p5 | H100 | 80 GB |
The memory requirements will quickly exceed the memory available on a single instance type, hence the need to use parallelism technique which we’ll cover in a later post.
Inference
Training