Conversation
Summary of ChangesHello @michaelwithu, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed! This pull request introduces the foundational components for Native Sparse Attention (NSA) within the project. It delivers a Highlights
🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console. Using Gemini Code AssistThe full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips. Invoking Gemini You can request assistance from Gemini at any point by creating a comment using either
Customization To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a Limitations & Feedback Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here. You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension. Footnotes
|
There was a problem hiding this comment.
Code Review
This pull request introduces the forward pass for Native Sparse Attention (NSA), including the TileLang kernel, op/function/layer wrappers, and benchmarks. It also adds a mean pooling kernel in TileLang, verified against a Triton implementation. The overall structure is good, following the existing TileOps hierarchy. However, there's a significant amount of temporary and test code committed within the library files, which should be removed or moved to the tests directory as noted in the TODOs. I've also identified a potential bug in the nsa_fwd kernel that limits the head dimension and some areas for improvement in the benchmark code.
top/kernels/deepseek_nsa/nsa_fwd.py
Outdated
|
|
||
| NK = tilelang.cdiv(dim, block_T) | ||
| NV = tilelang.cdiv(dim, block_T) | ||
| assert NK == 1, "The key dimension can not be larger than 256" |
There was a problem hiding this comment.
The assertion assert NK == 1 will fail if the head dimension dim is larger than block_T. Given that block_T is at most 128, this kernel will not work for dim > 128. This is a significant limitation and should be fixed to support larger head dimensions. The comment "The key dimension can not be larger than 256" is also misleading.
| H, D, chunk_size = 4, 64, 32 | ||
|
|
||
| x_unpad = torch.randn(total_T, H, D, dtype=torch.float16, device=device) | ||
| # x_triton = x_unpad.unsqueeze(0) # (1, total_T, H, D) |
| import torch | ||
| import top | ||
| from top import MLAKernel | ||
|
|
||
| device = "cuda" | ||
| dtype = torch.float16 | ||
|
|
||
| batch = 128 | ||
| heads = 64 | ||
| kv_heads = 1 | ||
| kv_ctx = 8192 | ||
| dim = 512 | ||
| pe_dim = 64 | ||
|
|
||
| # Query input: [batch, heads, dim] | ||
| q = torch.randn(batch, heads, dim, device=device, dtype=dtype) | ||
|
|
||
| # Query positional encoding: [batch, heads, pe_dim] | ||
| q_pe = torch.randn(batch, heads, pe_dim, device=device, dtype=dtype) | ||
|
|
||
| # KV cache input: [batch, kv_ctx, kv_heads, dim] | ||
| kv = torch.randn(batch, kv_ctx, kv_heads, dim, device=device, dtype=dtype) | ||
|
|
||
| # KV positional encoding: [batch, kv_ctx, kv_heads, pe_dim] | ||
| k_pe = torch.randn(batch, kv_ctx, kv_heads, pe_dim, device=device, dtype=dtype) | ||
|
|
||
| # Use MLA kernel | ||
| block_N = 64 | ||
| block_H = 64 | ||
| num_split = 1 | ||
|
|
||
| mla = MLAKernel(batch, heads, kv_heads, kv_ctx, dim, pe_dim, block_N, block_H, num_split) | ||
|
|
||
| out = mla(q, q_pe, kv, k_pe) |
| block_size=64, | ||
| groups=1, | ||
| selected_blocks=16, | ||
| # dtype='float16', |
top/functions/deepseek_nsa.py
Outdated
| # def main(): | ||
| # B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 64, 1, 16, 32, 1, 32, torch.float16, 0.1 | ||
|
|
||
| # block_T = min(128, 16) | ||
|
|
||
| # kernel = NativeSparseAttentionFunc( | ||
| # batch=B, | ||
| # heads=HQ, | ||
| # seq_len=SEQ_LEN, | ||
| # dim=D, | ||
| # is_causal=True, | ||
| # block_size=block_size, | ||
| # groups=HQ // H, | ||
| # selected_blocks=S, | ||
| # scale=scale, | ||
| # tune=True, | ||
| # ) | ||
|
|
||
|
|
||
| # torch.random.manual_seed(0) | ||
| # Q = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| # K = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| # V = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| # g_slc = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| # g_swa = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| # DO = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda") | ||
|
|
||
| # block_indices = torch.full((B, SEQ_LEN, H, S), SEQ_LEN, dtype=torch.long, device="cuda") | ||
| # block_counts = torch.zeros((B, SEQ_LEN, H), dtype=torch.long, device="cuda") | ||
| # for b in range(B): | ||
| # for t in range(SEQ_LEN): | ||
| # for h in range(H): | ||
| # i_i = torch.randperm(max(1, (t // block_size)))[:S] | ||
| # block_indices[b, t, h, : len(i_i)] = i_i | ||
| # block_counts[b, t, h] = (block_indices[b, t, h] != SEQ_LEN).sum().item() | ||
| # block_indices = block_indices.sort(-1)[0] | ||
|
|
||
| # out = kernel.forward(Q, K, V, block_indices.to(torch.int32)) | ||
|
|
||
| # ref = naive_nsa( | ||
| # q=Q, | ||
| # k=K, | ||
| # v=V, | ||
| # g_slc=g_slc, | ||
| # g_swa=g_swa, | ||
| # block_indices=block_indices, | ||
| # block_counts=block_counts, | ||
| # block_size=block_size, | ||
| # scale=scale, | ||
| # ) | ||
|
|
||
| # print("out", out) | ||
| # print("ref", ref) | ||
| # torch.testing.assert_close(ref, out, atol=1e-2, rtol=1e-2) | ||
|
|
||
|
|
||
| # if __name__ == "__main__": | ||
| # main() No newline at end of file |
top/kernels/deepseek_nsa/nsa_fwd.py
Outdated
| def main(): | ||
| # B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 64, 1, 16, 32, 1, 32, torch.float16, 0.1 | ||
| B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 8192, 4, 16*4, 128, 16, 32, torch.float16, 0.1 | ||
|
|
||
| block_T = min(128, tilelang.math.next_power_of_2(D)) | ||
| kernel = _nsa_fwd_kernel( | ||
| batch=B, | ||
| heads=HQ, | ||
| seq_len=SEQ_LEN, | ||
| dim=D, | ||
| is_causal=True, | ||
| scale=scale, | ||
| block_size=block_size, | ||
| groups=HQ // H, | ||
| selected_blocks=S, | ||
| )(block_T=block_T, num_stages=2, threads=32) | ||
|
|
||
| kernel2 = nsa_fwd_kernel( | ||
| batch=B, | ||
| heads=HQ, | ||
| seq_len=SEQ_LEN, | ||
| dim=D, | ||
| is_causal=True, | ||
| block_size=block_size, | ||
| groups=HQ // H, | ||
| selected_blocks=S, | ||
| scale=scale, | ||
| tune=True, | ||
| ) | ||
|
|
||
|
|
||
| src_kernel = kernel.get_kernel_source() | ||
| print(src_kernel) | ||
| # with open("nsa_fwd_kernel.cu", "w") as f: | ||
| # f.write(src_kernel) | ||
| torch.random.manual_seed(0) | ||
| Q = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| K = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| V = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_slc = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_swa = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| DO = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda") | ||
|
|
||
| block_indices = torch.full((B, SEQ_LEN, H, S), SEQ_LEN, dtype=torch.long, device="cuda") | ||
| block_counts = torch.zeros((B, SEQ_LEN, H), dtype=torch.long, device="cuda") | ||
| for b in range(B): | ||
| for t in range(SEQ_LEN): | ||
| for h in range(H): | ||
| i_i = torch.randperm(max(1, (t // block_size)))[:S] | ||
| block_indices[b, t, h, : len(i_i)] = i_i | ||
| block_counts[b, t, h] = (block_indices[b, t, h] != SEQ_LEN).sum().item() | ||
| block_indices = block_indices.sort(-1)[0] | ||
|
|
||
| out = kernel(Q, K, V, block_indices.to(torch.int32)) | ||
|
|
||
| out2 = kernel2.forward(Q, K, V, block_indices.to(torch.int32)) | ||
|
|
||
|
|
||
| if __name__ == "__main__": | ||
| main() |
top/kernels/deepseek_nsa/nsa_fwd.py
Outdated
| # with open("nsa_fwd_kernel.cu", "w") as f: | ||
| # f.write(src_kernel) |
top/layers/deepseek_nsa.py
Outdated
| def main(): | ||
| B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 64, 1, 16, 32, 1, 32, torch.float16, 0.1 | ||
|
|
||
| block_T = min(128, 16) | ||
|
|
||
| kernel = NativeSparseAttentionLayer( | ||
| batch=B, | ||
| heads=HQ, | ||
| seq_len=SEQ_LEN, | ||
| dim=D, | ||
| is_causal=True, | ||
| block_size=block_size, | ||
| groups=HQ // H, | ||
| selected_blocks=S, | ||
| scale=scale, | ||
| tune=True, | ||
| ) | ||
|
|
||
|
|
||
| torch.random.manual_seed(0) | ||
| Q = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| K = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| V = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_slc = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_swa = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| DO = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda") | ||
|
|
||
| block_indices = torch.full((B, SEQ_LEN, H, S), SEQ_LEN, dtype=torch.long, device="cuda") | ||
| block_counts = torch.zeros((B, SEQ_LEN, H), dtype=torch.long, device="cuda") | ||
| for b in range(B): | ||
| for t in range(SEQ_LEN): | ||
| for h in range(H): | ||
| i_i = torch.randperm(max(1, (t // block_size)))[:S] | ||
| block_indices[b, t, h, : len(i_i)] = i_i | ||
| block_counts[b, t, h] = (block_indices[b, t, h] != SEQ_LEN).sum().item() | ||
| block_indices = block_indices.sort(-1)[0] | ||
|
|
||
| out = kernel.forward(Q, K, V, block_indices.to(torch.int32)) | ||
|
|
||
| ref = naive_nsa( | ||
| q=Q, | ||
| k=K, | ||
| v=V, | ||
| g_slc=g_slc, | ||
| g_swa=g_swa, | ||
| block_indices=block_indices, | ||
| block_counts=block_counts, | ||
| block_size=block_size, | ||
| scale=scale, | ||
| ) | ||
|
|
||
| print("out", out) | ||
| print("ref", ref) | ||
| torch.testing.assert_close(ref, out, atol=1e-2, rtol=1e-2) | ||
|
|
||
|
|
||
| if __name__ == "__main__": | ||
| main() No newline at end of file |
top/ops/deepseek_nsa.py
Outdated
| print("batch ", self.batch) | ||
| print("heads ", self.heads) | ||
| print("seq_len ", self.seq_len) | ||
| print("dim ", self.dim) | ||
| print("is_causal ", self.is_causal) | ||
| print("scale ", self.scale) | ||
| print("block_size ", self.block_size) | ||
| print("groups ", self.groups) | ||
| print("selected_blocks ", self.selected_blocks) | ||
| print("tune ", self.tune) |
top/ops/deepseek_nsa.py
Outdated
| def main(): | ||
| # B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 64, 1, 16, 32, 1, 32, torch.float16, 0.1 | ||
|
|
||
| B, SEQ_LEN, H, HQ, D, S, block_size, dtype, scale = 2, 8192, 4, 16*4, 128, 16, 32, torch.float16, 0.1 | ||
|
|
||
| block_T = min(128, 16) | ||
|
|
||
| kernel = NativeSparseAttentionForwardOp( | ||
| batch=B, | ||
| heads=HQ, | ||
| seq_len=SEQ_LEN, | ||
| dim=D, | ||
| is_causal=True, | ||
| block_size=block_size, | ||
| groups=HQ // H, | ||
| selected_blocks=S, | ||
| scale=scale, | ||
| tune=True, | ||
| ) | ||
|
|
||
|
|
||
| torch.random.manual_seed(0) | ||
| Q = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| K = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| V = torch.randn((B, SEQ_LEN, H, D), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_slc = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| g_swa = torch.ones((B, SEQ_LEN, HQ), dtype=dtype, device="cuda").requires_grad_(True) | ||
| DO = torch.randn((B, SEQ_LEN, HQ, D), dtype=dtype, device="cuda") | ||
|
|
||
| block_indices = torch.full((B, SEQ_LEN, H, S), SEQ_LEN, dtype=torch.long, device="cuda") | ||
| block_counts = torch.zeros((B, SEQ_LEN, H), dtype=torch.long, device="cuda") | ||
| for b in range(B): | ||
| for t in range(SEQ_LEN): | ||
| for h in range(H): | ||
| i_i = torch.randperm(max(1, (t // block_size)))[:S] | ||
| block_indices[b, t, h, : len(i_i)] = i_i | ||
| block_counts[b, t, h] = (block_indices[b, t, h] != SEQ_LEN).sum().item() | ||
| block_indices = block_indices.sort(-1)[0] | ||
|
|
||
| out = kernel.forward(Q, K, V, block_indices.to(torch.int32)) | ||
|
|
||
| # ref = naive_nsa( | ||
| # q=Q, | ||
| # k=K, | ||
| # v=V, | ||
| # g_slc=g_slc, | ||
| # g_swa=g_swa, | ||
| # block_indices=block_indices, | ||
| # block_counts=block_counts, | ||
| # block_size=block_size, | ||
| # scale=scale, | ||
| # ) | ||
|
|
||
| print("out", out) | ||
| # print("ref", ref) | ||
| # torch.testing.assert_close(ref, out, atol=1e-2, rtol=1e-2) | ||
|
|
||
|
|
||
| if __name__ == "__main__": | ||
| main() No newline at end of file |
resolve #70
todo: