diff --git a/csrc/attention.cpp b/csrc/attention.cpp index bb2766c1d6b6..57dff9dc0b2b 100644 --- a/csrc/attention.cpp +++ b/csrc/attention.cpp @@ -11,9 +11,25 @@ void single_query_cached_kv_attention( int block_size, int max_context_len); +void multi_query_cached_kv_attention( + torch::Tensor& cu_query_lens, + torch::Tensor& out, + torch::Tensor& query, + torch::Tensor& key_cache, + torch::Tensor& value_cache, + float scale, + torch::Tensor& block_tables, + torch::Tensor& context_lens, + int block_size, + int max_context_len); + PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) { m.def( "single_query_cached_kv_attention", &single_query_cached_kv_attention, "Compute the attention between an input query and the cached key/value tensors"); + m.def( + "multi_query_cached_kv_attention", + &multi_query_cached_kv_attention, + "Compute the attention between multiple input queries and the cached key/value tensors"); } diff --git a/csrc/attention_kernels.cu b/csrc/attention_kernels.cu index 60c0d0c6cd03..73c29b745309 100644 --- a/csrc/attention_kernels.cu +++ b/csrc/attention_kernels.cu @@ -254,6 +254,287 @@ __global__ void single_query_cached_kv_attention_kernel( } } + +// Grid: (num_heads, num_query_tokens). +template< + typename scalar_t, + int HEAD_SIZE, + int BLOCK_SIZE, + int NUM_THREADS> +__device__ void multi_query_cached_kv_attention_kernel_unoptimized_( + scalar_t* __restrict__ out, // [num_seqs, num_heads, head_size] + const scalar_t* __restrict__ q, // [num_seqs, num_heads, head_size] + const int seq_start_idx, + const int seq_len, + const scalar_t* __restrict__ k_cache, // [num_blocks, num_heads, head_size/x, block_size, x] + const scalar_t* __restrict__ v_cache, // [num_blocks, num_heads, head_size, block_size] + const float scale, + const int* __restrict__ block_table, // [num_seqs, max_num_blocks_per_seq] + const int context_len, + const int max_num_blocks_per_seq) { + constexpr int THREAD_GROUP_SIZE = WARP_SIZE / BLOCK_SIZE; + constexpr int NUM_WARPS = NUM_THREADS / WARP_SIZE; + const int thread_idx = threadIdx.x; + const int warp_idx = thread_idx / WARP_SIZE; + const int lane = thread_idx % WARP_SIZE; + + const int head_idx = blockIdx.x; + const int num_heads = gridDim.x; + const int seq_idx = blockIdx.y; + + // A vector type to store a part of a key or a query. + // The vector size is configured in such a way that the threads in a thread group + // fetch or comput 16 bytes at a time. + // For example, if the size of a thread group is 4 and the data type is half, + // then the vector size is 16 / (4 * sizeof(half)) == 2. + constexpr int VEC_SIZE = 16 / (THREAD_GROUP_SIZE * sizeof(scalar_t)); + using K_vec = typename Vec::Type; + using Q_vec = typename Vec::Type; + + constexpr int NUM_ELEMS_PER_THREAD = HEAD_SIZE / THREAD_GROUP_SIZE; + constexpr int NUM_VECS_PER_THREAD = NUM_ELEMS_PER_THREAD / VEC_SIZE; + + const int thread_group_idx = thread_idx / THREAD_GROUP_SIZE; + const int thread_group_offset = thread_idx % THREAD_GROUP_SIZE; + + // Load the query to registers. + // Each thread in a thread group has a different part of the query. + // For example, if the the thread group size is 4, then the first thread in the group + // has 0, 4, 8, ... th vectors of the query, and the second thread has 1, 5, 9, ... + // th vectors of the query, and so on. + const scalar_t* q_ptr = q + seq_idx * num_heads * HEAD_SIZE + head_idx * HEAD_SIZE; + Q_vec q_vecs[NUM_VECS_PER_THREAD]; +#pragma unroll + for (int i = 0; i < NUM_VECS_PER_THREAD; i++) { + const int vec_idx = thread_group_offset + i * THREAD_GROUP_SIZE; + q_vecs[i] = *reinterpret_cast(q_ptr + vec_idx * VEC_SIZE); + } + + // Memory planning. + extern __shared__ char shared_mem[]; + // NOTE(woosuk): We use FP32 logits and accumulation. + float *logits = reinterpret_cast(shared_mem); + // Workspace for reduction. + __shared__ float red_smem[2 * NUM_WARPS]; + + // x == THREAD_GROUP_SIZE * VEC_SIZE + // Each thread group fetches x elements from the key at a time. + constexpr int x = 16 / sizeof(scalar_t); + float qk_max = -FLT_MAX; + + const int num_blocks = (context_len + BLOCK_SIZE - 1) / BLOCK_SIZE; + const int mask_boundary = context_len - seq_len + 1 + (seq_idx - seq_start_idx); + + // Iterate over the key blocks. + // Each warp fetches a block of keys for each iteration. + // Each thread group in a warp fetches a key from the block, and computes + // dot product with the query. + for (int block_idx = warp_idx; block_idx < num_blocks; block_idx += NUM_WARPS) { + const int physical_block_number = block_table[block_idx]; + const int physical_block_offset = thread_group_idx % BLOCK_SIZE; + const int token_idx = block_idx * BLOCK_SIZE + physical_block_offset; + + // Load a key to registers. + // Each thread in a thread group has a different part of the key. + // For example, if the the thread group size is 4, then the first thread in the group + // has 0, 4, 8, ... th vectors of the key, and the second thread has 1, 5, 9, ... th + // vectors of the key, and so on. + K_vec k_vecs[NUM_VECS_PER_THREAD]; +#pragma unroll + for (int i = 0; i < NUM_VECS_PER_THREAD; i++) { + const scalar_t* k_ptr = k_cache + physical_block_number * num_heads * HEAD_SIZE * BLOCK_SIZE + + head_idx * HEAD_SIZE * BLOCK_SIZE + + physical_block_offset * x; + const int vec_idx = thread_group_offset + i * THREAD_GROUP_SIZE; + const int offset1 = (vec_idx * VEC_SIZE) / x; + const int offset2 = (vec_idx * VEC_SIZE) % x; + k_vecs[i] = *reinterpret_cast(k_ptr + offset1 * BLOCK_SIZE * x + offset2); + } + + // Compute dot product. + // This includes a reduction across the threads in the same thread group. + const float qk = scale * Qk_dot::dot(q_vecs, k_vecs); + const bool mask = token_idx >= mask_boundary; + + if (thread_group_offset == 0) { + // Store the partial reductions to shared memory. + // NOTE(woosuk): It is required to zero out the masked logits. + logits[token_idx] = mask ? 0.f : qk; + // Update the max value. + qk_max = mask ? qk_max : fmaxf(qk_max, qk); + } + } + + // Perform reduction across the threads in the same warp to get the + // max qk value for each "warp" (not across the thread block yet). + // The 0-th thread of each thread group already has its max qk value. +#pragma unroll + for (int mask = WARP_SIZE / 2; mask >= THREAD_GROUP_SIZE; mask /= 2) { + qk_max = fmaxf(qk_max, __shfl_xor_sync(uint32_t(-1), qk_max, mask)); + } + if (lane == 0) { + red_smem[warp_idx] = qk_max; + } + __syncthreads(); + + // TODO(woosuk): Refactor this part. + // Get the max qk value for the sequence. + qk_max = lane < NUM_WARPS ? red_smem[lane] : -FLT_MAX; +#pragma unroll + for (int mask = NUM_WARPS / 2; mask >= 1; mask /= 2) { + qk_max = fmaxf(qk_max, __shfl_xor_sync(uint32_t(-1), qk_max, mask)); + } + // Broadcast the max qk value to all threads. + qk_max = __shfl_sync(uint32_t(-1), qk_max, 0); + + // Get the sum of the exp values. + float exp_sum = 0.f; + for (int i = thread_idx; i < mask_boundary; i += NUM_THREADS) { + float val = __expf(logits[i] - qk_max); + logits[i] = val; + exp_sum += val; + } + exp_sum = block_sum(&red_smem[NUM_WARPS], exp_sum); + + // Compute softmax. + const float inv_sum = __fdividef(1.f, exp_sum + 1e-6f); + for (int i = thread_idx; i < context_len; i += NUM_THREADS) { + logits[i] *= inv_sum; + } + __syncthreads(); + + // Each thread will fetch 16 bytes from the value cache at a time. + constexpr int V_VEC_SIZE = 16 / sizeof(scalar_t); + using V_vec = typename Vec::Type; + using L_vec = typename FloatVec::Type; + + constexpr int NUM_V_VECS_PER_ROW = BLOCK_SIZE / V_VEC_SIZE; + constexpr int NUM_ROWS_PER_ITER = WARP_SIZE / NUM_V_VECS_PER_ROW; + constexpr int NUM_ROWS_PER_THREAD = (HEAD_SIZE + NUM_ROWS_PER_ITER - 1) / NUM_ROWS_PER_ITER; + + float accs[NUM_ROWS_PER_THREAD]; +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + accs[i] = 0.f; + } + + for (int block_idx = warp_idx; block_idx < num_blocks; block_idx += NUM_WARPS) { + const int physical_block_number = block_table[block_idx]; + const int physical_block_offset = (lane % NUM_V_VECS_PER_ROW) * V_VEC_SIZE; + const int token_idx = block_idx * BLOCK_SIZE + physical_block_offset; + L_vec logits_vec = *reinterpret_cast(logits + token_idx); + + const scalar_t* v_ptr = v_cache + physical_block_number * num_heads * HEAD_SIZE * BLOCK_SIZE + + head_idx * HEAD_SIZE * BLOCK_SIZE; +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + const int row_idx = lane / NUM_V_VECS_PER_ROW + i * NUM_ROWS_PER_ITER; + if (row_idx < HEAD_SIZE) { + const int offset = row_idx * BLOCK_SIZE + physical_block_offset; + V_vec v_vec = *reinterpret_cast(v_ptr + offset); + accs[i] += dot(logits_vec, cast_to_float(v_vec)); + } + } + } + + // Perform reduction within each warp. +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + float acc = accs[i]; +#pragma unroll + for (int mask = NUM_V_VECS_PER_ROW / 2; mask >= 1; mask /= 2) { + acc += __shfl_xor_sync(uint32_t(-1), acc, mask); + } + accs[i] = acc; + } + + // NOTE(woosuk): A barrier is required because the shared memory space for logits + // is reused for the output. + __syncthreads(); + + // Perform reduction across warps. + float* out_smem = reinterpret_cast(shared_mem); +#pragma unroll + for (int i = NUM_WARPS; i > 1; i /= 2) { + int mid = i / 2; + // Upper warps write to shared memory. + if (warp_idx >= mid && warp_idx < i) { + float* dst = &out_smem[(warp_idx - mid) * HEAD_SIZE]; +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + const int row_idx = lane / NUM_V_VECS_PER_ROW + i * NUM_ROWS_PER_ITER; + if (row_idx < HEAD_SIZE && lane % NUM_V_VECS_PER_ROW == 0) { + dst[row_idx] = accs[i]; + } + } + } + __syncthreads(); + + // Lower warps update the output. + if (warp_idx < mid) { + const float* src = &out_smem[warp_idx * HEAD_SIZE]; +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + const int row_idx = lane / NUM_V_VECS_PER_ROW + i * NUM_ROWS_PER_ITER; + if (row_idx < HEAD_SIZE && lane % NUM_V_VECS_PER_ROW == 0) { + accs[i] += src[row_idx]; + } + } + } + __syncthreads(); + } + + // Write the final output. + if (warp_idx == 0) { + scalar_t* out_ptr = out + seq_idx * num_heads * HEAD_SIZE + head_idx * HEAD_SIZE; +#pragma unroll + for (int i = 0; i < NUM_ROWS_PER_THREAD; i++) { + const int row_idx = lane / NUM_V_VECS_PER_ROW + i * NUM_ROWS_PER_ITER; + if (row_idx < HEAD_SIZE && lane % NUM_V_VECS_PER_ROW == 0) { + convert_from_float(*(out_ptr + row_idx), accs[i]); + } + } + } +} + + +// Grid: (num_heads, num_query_tokens). +template< + typename scalar_t, + int HEAD_SIZE, + int BLOCK_SIZE, + int NUM_THREADS> +__global__ void multi_query_cached_kv_attention_kernel( + const int* cu_query_lens, // [num_prompts+1] + const int* seq_prompt_mapping, // [num_seqs] mapping from seq_idx to prompt_idx + scalar_t* __restrict__ out, // [num_seqs, num_heads, head_size] + const scalar_t* __restrict__ q, // [num_seqs, num_heads, head_size] + const scalar_t* __restrict__ k_cache, // [num_blocks, num_heads, head_size/x, block_size, x] + const scalar_t* __restrict__ v_cache, // [num_blocks, num_heads, head_size, block_size] + const float scale, + const int* __restrict__ block_tables, // [num_prompts, max_num_blocks_per_seq] + const int* __restrict__ context_lens, // [num_prompts] + const int max_num_blocks_per_seq) { + const int seq_idx = blockIdx.y; + const int prompt_idx = seq_prompt_mapping[seq_idx]; + const int seq_start_idx = cu_query_lens[prompt_idx]; + const int seq_len = cu_query_lens[prompt_idx + 1] - seq_start_idx; + const int* block_table = block_tables + prompt_idx * max_num_blocks_per_seq; + const int context_len = context_lens[prompt_idx]; + multi_query_cached_kv_attention_kernel_unoptimized_< + scalar_t, HEAD_SIZE, BLOCK_SIZE, NUM_THREADS>( + out, + q, + seq_start_idx, + seq_len, + k_cache, + v_cache, + scale, + block_table, + context_len, + max_num_blocks_per_seq); +} + } // namespace cacheflow #define LAUNCH_ATTENTION_KERNEL(T, HEAD_SIZE, BLOCK_SIZE, NUM_THREADS) \ @@ -402,4 +683,186 @@ void single_query_cached_kv_attention( } } + +#define LAUNCH_MULTI_ATTENTION_KERNEL(T, HEAD_SIZE, BLOCK_SIZE, NUM_THREADS) \ + cacheflow::multi_query_cached_kv_attention_kernel \ + <<>>( \ + cu_query_lens_ptr, \ + seq_prompt_mapping_ptr, \ + out_ptr, \ + query_ptr, \ + key_cache_ptr, \ + value_cache_ptr, \ + scale, \ + block_tables_ptr, \ + context_lens_ptr, \ + max_num_blocks_per_seq); + + +// TODO(woosuk): Tune NUM_THREADS. +template< + typename T, + int BLOCK_SIZE, + int NUM_THREADS = 128> +void multi_query_cached_kv_attention_launcher( + torch::Tensor& cu_query_lens, + torch::Tensor& seq_prompt_mapping, + torch::Tensor& out, + torch::Tensor& query, + torch::Tensor& key_cache, + torch::Tensor& value_cache, + float scale, + torch::Tensor& block_tables, + torch::Tensor& context_lens, + int max_context_len) { + int num_seqs = query.size(0); + int num_heads = query.size(1); + int head_size = query.size(2); + int max_num_blocks_per_seq = block_tables.size(1); + + int* cu_query_lens_ptr = cu_query_lens.data_ptr(); + int* seq_prompt_mapping_ptr = seq_prompt_mapping.data_ptr(); + T* out_ptr = reinterpret_cast(out.data_ptr()); + T* query_ptr = reinterpret_cast(query.data_ptr()); + T* key_cache_ptr = reinterpret_cast(key_cache.data_ptr()); + T* value_cache_ptr = reinterpret_cast(value_cache.data_ptr()); + int* block_tables_ptr = block_tables.data_ptr(); + int* context_lens_ptr = context_lens.data_ptr(); + + constexpr int NUM_WARPS = NUM_THREADS / WARP_SIZE; + int padded_max_context_len = ((max_context_len + BLOCK_SIZE - 1) / BLOCK_SIZE) * BLOCK_SIZE; + int logits_size = padded_max_context_len * sizeof(float); + int outputs_size = (NUM_WARPS / 2) * head_size * sizeof(float); + int shared_mem_size = std::max(logits_size, outputs_size); + + dim3 grid(num_heads, num_seqs); + dim3 block(NUM_THREADS); + const cudaStream_t stream = at::cuda::getCurrentCUDAStream(); + switch (head_size) { + case 32: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 32, BLOCK_SIZE, NUM_THREADS); + break; + case 64: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 64, BLOCK_SIZE, NUM_THREADS); + break; + case 80: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 80, BLOCK_SIZE, NUM_THREADS); + break; + case 96: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 96, BLOCK_SIZE, NUM_THREADS); + break; + case 128: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 128, BLOCK_SIZE, NUM_THREADS); + break; + case 160: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 160, BLOCK_SIZE, NUM_THREADS); + break; + case 192: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 192, BLOCK_SIZE, NUM_THREADS); + break; + case 256: + LAUNCH_MULTI_ATTENTION_KERNEL(T, 256, BLOCK_SIZE, NUM_THREADS); + break; + default: + assert(false); + break; + } +} + +void multi_query_cached_kv_attention( + torch::Tensor& cu_query_lens, + torch::Tensor& out, + torch::Tensor& query, + torch::Tensor& key_cache, + torch::Tensor& value_cache, + float scale, + torch::Tensor& block_tables, + torch::Tensor& context_lens, + int block_size, + int max_context_len) { + + torch::Tensor query_lens = cu_query_lens.to(torch::kCPU); + + int num_queries = query_lens.size(0) - 1; + const int* query_lens_ptr = query_lens.data_ptr(); + int num_seqs = query.size(0); + + torch::Tensor cpu_tensor = torch::empty({num_seqs}, torch::dtype(torch::kInt32)); + auto accessor = cpu_tensor.accessor(); + for (int i = 0, query_cursor = 0; i < num_seqs; ++i) { + if (i >= query_lens_ptr[query_cursor + 1]) { + ++query_cursor; + } + accessor[i] = query_cursor; + } + + // TODO(suquark): This can be slow, as it to(torch::kCPU) and to(torch::kCUDA) + // implicitly synchronizes the CPU and GPU. And we can avoid this issue by giving + // the mapping as an input parameter. Let's do this optimization in a later PR. + torch::Tensor seq_prompt_mapping = cpu_tensor.to(torch::kCUDA); + + // TODO(woosuk): Support BF16. + if (query.element_size() == 2) { + // Half. + if (block_size == 8) { + multi_query_cached_kv_attention_launcher( + cu_query_lens, + seq_prompt_mapping, + out, + query, + key_cache, + value_cache, + scale, + block_tables, + context_lens, + max_context_len); + } else if (block_size == 16) { + multi_query_cached_kv_attention_launcher( + cu_query_lens, + seq_prompt_mapping, + out, + query, + key_cache, + value_cache, + scale, + block_tables, + context_lens, + max_context_len); + } else { + assert(false); + } + } else if (query.element_size() == 4) { + // Float. + if (block_size == 8) { + multi_query_cached_kv_attention_launcher( + cu_query_lens, + seq_prompt_mapping, + out, + query, + key_cache, + value_cache, + scale, + block_tables, + context_lens, + max_context_len); + } else if (block_size == 16) { + multi_query_cached_kv_attention_launcher( + cu_query_lens, + seq_prompt_mapping, + out, + query, + key_cache, + value_cache, + scale, + block_tables, + context_lens, + max_context_len); + } else { + assert(false); + } + } else { + assert(false); + } +} + #undef WARP_SIZE diff --git a/tests/kernels/attention.py b/tests/kernels/attention.py index 409da9efa2ef..0747566eb278 100644 --- a/tests/kernels/attention.py +++ b/tests/kernels/attention.py @@ -97,6 +97,61 @@ def ref_multi_query_kv_attention( return ref_output +def ref_multi_query_cached_kv_attention( + cu_query_lens: List[int], + query: torch.Tensor, + key_cache: torch.Tensor, + value_cache: torch.Tensor, + block_tables: torch.Tensor, + context_lens: torch.Tensor, + dtype: torch.dtype, +) -> torch.Tensor: + num_heads = value_cache.shape[1] + head_size = value_cache.shape[2] + block_size = value_cache.shape[3] + scale = 1.0 / (head_size ** 0.5) + + num_queries = len(cu_query_lens) - 1 + ref_outputs = [] + for i in range(num_queries): + start_idx = cu_query_lens[i] + end_idx = cu_query_lens[i + 1] + query_len = end_idx - start_idx + context_len = int(context_lens[i]) + block_table = block_tables[i] + + # Create attention mask + attn_mask = torch.triu( + torch.ones(query_len, context_len), diagonal=context_len - query_len + 1) * -1e5 + attn_mask = attn_mask.to(dtype=dtype, device='cuda') + + keys = [] + values = [] + for j in range(context_len): + block_number = int(block_table[j // block_size]) + block_offset = j % block_size + + k = key_cache[block_number, :, :, block_offset, :] + k = k.reshape(num_heads, head_size) + keys.append(k) + + v = value_cache[block_number, :, :, block_offset] + values.append(v) + keys = torch.stack(keys, dim=0) + values = torch.stack(values, dim=0) + + ref_output = ref_masked_attention( + query[start_idx:end_idx], + keys, + values, + scale, + attn_mask=attn_mask, + ) + ref_outputs.append(ref_output) + ref_output = torch.cat(ref_outputs, dim=0) + return ref_output + + def test_single_query_cached_kv_attention( num_tokens: int, num_heads: int, @@ -216,6 +271,76 @@ def test_multi_query_kv_attention( assert torch.allclose(output, ref_output, atol=1e-3, rtol=1e-5) +def test_multi_query_cached_kv_attention( + num_queries: int, + num_heads: int, + head_size: int, + block_size: int, + num_blocks: int, + dtype: torch.dtype, +) -> None: + query_lens = random.sample(range(1, MAX_SEQ_LEN), num_queries) + cu_query_lens = [0] + for query_len in query_lens: + cu_query_lens.append(cu_query_lens[-1] + query_len) + num_total_tokens = cu_query_lens[-1] + + query = torch.randn( + num_total_tokens, num_heads, head_size, dtype=dtype, device='cuda') + x = 16 // torch.tensor([], dtype=dtype).element_size() + key_block_shape = (num_heads, head_size // x, block_size, x) + key_cache = torch.randn( + size=(num_blocks, *key_block_shape), dtype=dtype, device='cuda') + value_block_shape = (num_heads, head_size, block_size) + value_cache = torch.randn( + size=(num_blocks, *value_block_shape), dtype=dtype, device='cuda') + + cu_query_lens = torch.tensor(cu_query_lens, dtype=torch.int, device='cuda') + context_lens = [ + query_len + random.randint(0, MAX_SEQ_LEN - query_len) + for query_len in query_lens + ] + max_context_len = max(context_lens) + context_lens = torch.tensor(context_lens, dtype=torch.int, device='cuda') + + max_num_blocks_per_seq = (max_context_len + block_size - 1) // block_size + block_tables = [] + for _ in range(num_queries): + block_table = [ + random.randint(0, num_blocks - 1) + for _ in range(max_num_blocks_per_seq) + ] + block_tables.append(block_table) + block_tables = torch.tensor(block_tables, dtype=torch.int, device='cuda') + + scale = float(1.0 / (head_size ** 0.5)) + output = torch.empty_like(query) + + attention_ops.multi_query_cached_kv_attention( + cu_query_lens, + output, + query, + key_cache, + value_cache, + scale, + block_tables, + context_lens, + block_size, + max_context_len, + ) + + ref_output = ref_multi_query_cached_kv_attention( + cu_query_lens, + query, + key_cache, + value_cache, + block_tables, + context_lens, + dtype, + ) + assert torch.allclose(output, ref_output, atol=1e-3, rtol=1e-5) + + @torch.inference_mode() def test_attention(seed: int) -> None: # NOTE(woosuk): Even when the seed is fixed, there is a chance that @@ -237,6 +362,24 @@ def test_attention(seed: int) -> None: dtype=dtype, ) + # NOTE(siyuan): Same as above. Re-run the test if it fails. Also + # note that the test is also more likely to fail due to the much + # larger amount of tokens in the input may increase the variance. + for dtype in [torch.half, torch.float]: + for block_size in [8, 16]: + for head_size in [32, 64, 80, 96, 128, 160, 192, 256]: + print(f'Testing multi_query_cached_kv_attention with ' + f'dtype={dtype}, block_size={block_size}, ' + f'head_size={head_size}') + test_multi_query_cached_kv_attention( + num_queries=11, + num_heads=3, + head_size=head_size, + block_size=block_size, + num_blocks=1024, + dtype=dtype, + ) + # NOTE(woosuk): FlashAttention does not support FP32. for dtype in [torch.half]: # NOTE(woosuk): FlashAttention does not support head_size > 128.