tacit/nanochat
1
0
Fork 0
mirror of https://github.com/karpathy/nanochat.git synced 2025-12-06 04:12:13 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

fix silly issue in dataloader, this version is much faster and more portable to mps too

Browse Source
This commit is contained in:
Andrej Karpathy 2025-10-21 17:12:50 +00:00
parent c9ea7a91e2
commit bb71c64579
1 changed files with 2 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
nanochat/dataloader.py
View File

@ -16,7 +16,6 @@ def tokenizing_distributed_data_loader(B, T, split, tokenizer_threads=4, tokeniz
bos_token = tokenizer.get_bos_token_id()
# scratch buffer holds the tokens for one iteration
token_buffer = deque() # we stream tokens on the right and pop from the left
scratch = torch.empty(needed_tokens, dtype=torch.int64, pin_memory=True)
# infinite iterator over document batches
def document_batches():
@ -38,8 +37,8 @@ def tokenizing_distributed_data_loader(B, T, split, tokenizer_threads=4, tokeniz
token_buffer.extend(tokens)
batch_index += 1
# Move tokens from the deque into the scratch buffer
for i in range(needed_tokens):
scratch[i] = token_buffer.popleft()
tokens = [token_buffer.popleft() for _ in range(needed_tokens)]
scratch = torch.tensor(tokens, dtype=torch.int64, pin_memory=True)
# Create the inputs/targets as 1D tensors
inputs_cpu = scratch[:-1].to(dtype=torch.int32)
targets_cpu = scratch[1:]