# SPDX-License-Identifier: Apache-2.0 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project import random import pytest import torch from vllm.attention import Attention from vllm.config import (CacheConfig, ModelConfig, ParallelConfig, SchedulerConfig, VllmConfig, set_current_vllm_config) from vllm.platforms import current_platform from vllm.sampling_params import SamplingParams from vllm.utils import GiB_bytes from vllm.v1.core.kv_cache_utils import (estimate_max_model_len, get_kv_cache_config) from vllm.v1.core.sched.output import (CachedRequestData, NewRequestData, SchedulerOutput) from vllm.v1.kv_cache_interface import (FullAttentionSpec, KVCacheConfig, KVCacheGroupSpec, KVCacheTensor) from vllm.v1.sample.metadata import SamplingMetadata from vllm.v1.worker.gpu_input_batch import InputBatch from vllm.v1.worker.gpu_model_runner import GPUModelRunner BLOCK_SIZE = 16 NUM_BLOCKS = 10 DEVICE = current_platform.device_type def initialize_kv_cache(runner: GPUModelRunner): """ Only perform necessary steps in GPUModelRunner.initialize_kv_cache() """ attn_spec = FullAttentionSpec( block_size=BLOCK_SIZE, num_kv_heads=runner.model_config.get_num_kv_heads( runner.parallel_config), head_size=runner.model_config.get_head_size(), dtype=runner.kv_cache_dtype, use_mla=False, ) tensor_size = attn_spec.page_size_bytes * NUM_BLOCKS kv_cache_config = KVCacheConfig( num_blocks=NUM_BLOCKS, kv_cache_tensors=[ KVCacheTensor(size=tensor_size, shared_by=["layer.0"]), ], kv_cache_groups=[ KVCacheGroupSpec(layer_names=["layer.0"], kv_cache_spec=attn_spec) ], ) runner.kv_cache_config = kv_cache_config runner.input_batch = InputBatch( max_num_reqs=runner.max_num_reqs, max_model_len=runner.max_model_len, max_num_batched_tokens=runner.max_num_tokens, device=runner.device, pin_memory=runner.pin_memory, vocab_size=runner.model_config.get_vocab_size(), block_sizes=[ kv_cache_config.kv_cache_groups[0].kv_cache_spec.block_size ], ) runner.initialize_attn_backend(kv_cache_config) def get_vllm_config(): scheduler_config = SchedulerConfig( max_num_seqs=10, max_num_batched_tokens=512, max_model_len=512, ) model_config = ModelConfig( model="facebook/opt-125m", task="generate", tokenizer="facebook/opt-125m", tokenizer_mode="auto", trust_remote_code=True, dtype="float16", seed=42, ) cache_config = CacheConfig( block_size=BLOCK_SIZE, gpu_memory_utilization=0.9, swap_space=0, cache_dtype="auto", ) parallel_config = ParallelConfig() vllm_config = VllmConfig( model_config=model_config, cache_config=cache_config, scheduler_config=scheduler_config, parallel_config=parallel_config, ) return vllm_config @pytest.fixture def model_runner(): vllm_config = get_vllm_config() model_config = vllm_config.model_config num_heads = model_config.get_num_kv_heads(vllm_config.parallel_config) head_size = model_config.get_head_size() vllm_config.compilation_config.static_forward_context[ "layer.0"] = Attention(num_heads, head_size, 0.1) runner = GPUModelRunner(vllm_config, DEVICE) initialize_kv_cache(runner) return runner model_runner_2 = model_runner def _schedule_new_request(*req_ids: str) -> SchedulerOutput: new_reqs = [] num_scheduled_tokens = {} total_num_scheduled_tokens = 0 for req_id in req_ids: new_reqs.append( NewRequestData( req_id=req_id, prompt_token_ids=[1, 2, 3], mm_inputs=[], mm_hashes=[], mm_positions=[], sampling_params=SamplingParams(), pooling_params=None, block_ids=([0], ), num_computed_tokens=0, lora_request=None, )) num_scheduled_tokens[req_id] = 3 total_num_scheduled_tokens += num_scheduled_tokens[req_id] return SchedulerOutput( scheduled_new_reqs=new_reqs, scheduled_cached_reqs=CachedRequestData.make_empty(), num_scheduled_tokens=num_scheduled_tokens, total_num_scheduled_tokens=total_num_scheduled_tokens, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids=set(), free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) def _is_req_scheduled(model_runner, req_id: str) -> bool: return req_id in model_runner.input_batch.req_id_to_index def _is_req_added(model_runner, req_id: str) -> bool: return req_id in model_runner.requests def _is_sampling_metadata_changed(model_runner, sampling_metadata_before: SamplingMetadata): return model_runner.input_batch.sampling_metadata is not ( sampling_metadata_before) def _is_req_state_block_table_match(model_runner, req_id: str) -> bool: req_index = model_runner.input_batch.req_id_to_index[req_id] block_table = model_runner.input_batch.block_table[0] req_state = model_runner.requests[req_id] if block_table.num_blocks_per_row[req_index] != len( req_state.block_ids[0]): return False num_blocks = block_table.num_blocks_per_row[req_index] return (block_table.block_table_np[req_index, :num_blocks] == req_state.block_ids[0]).all() def test_update_states_new_request(model_runner, dist_init): req_id = "req_0" # new req scheduler_output = _schedule_new_request(req_id) metadata_before = model_runner.input_batch.sampling_metadata model_runner._update_states(scheduler_output) assert _is_sampling_metadata_changed(model_runner, metadata_before) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) assert _is_req_state_block_table_match(model_runner, req_id) def test_update_states_request_finished(model_runner, dist_init): req_id = "req_0" # new req scheduler_output = _schedule_new_request(req_id) model_runner._update_states(scheduler_output) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) # finish req scheduler_output = SchedulerOutput( scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData.make_empty(), num_scheduled_tokens={}, total_num_scheduled_tokens=0, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids={req_id}, free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) metadata_before = model_runner.input_batch.sampling_metadata model_runner._update_states(scheduler_output) assert _is_sampling_metadata_changed(model_runner, metadata_before) assert not _is_req_added(model_runner, req_id) assert not _is_req_scheduled(model_runner, req_id) def test_update_states_request_resumed(model_runner, dist_init): req_id = "req_0" # new req scheduler_output = _schedule_new_request(req_id) model_runner._update_states(scheduler_output) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) # unschedule req scheduler_output = SchedulerOutput( scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData.make_empty(), num_scheduled_tokens={}, total_num_scheduled_tokens=0, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids=set(), free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) model_runner._update_states(scheduler_output) assert _is_req_added(model_runner, req_id) assert not _is_req_scheduled(model_runner, req_id) # resume req cached_req_data = CachedRequestData( req_ids=[req_id], resumed_from_preemption=[False], new_token_ids=[[]], new_block_ids=([[0]], ), num_computed_tokens=[0], ) scheduler_output = SchedulerOutput( scheduled_new_reqs=[], scheduled_cached_reqs=cached_req_data, num_scheduled_tokens={req_id: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids=set(), free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) metadata_before = model_runner.input_batch.sampling_metadata model_runner._update_states(scheduler_output) assert _is_sampling_metadata_changed(model_runner, metadata_before) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) assert _is_req_state_block_table_match(model_runner, req_id) def test_get_nans_in_logits(model_runner, dist_init): req_ids = ("req_0", "req_1") scheduler_output = _schedule_new_request(*req_ids) model_runner._update_states(scheduler_output) logits = torch.tensor([ [1.0, 2.0, 3.0], [3.0, 2.0, 1.0], ], device=DEVICE) result = model_runner._get_nans_in_logits(logits) assert result == {"req_0": 0, "req_1": 0} logits = torch.tensor([ [1.0, float('nan'), 3.0], [4.0, float('nan'), float('nan')], ], device=DEVICE) result = model_runner._get_nans_in_logits(logits) assert result == {"req_0": 1, "req_1": 2} logits = torch.tensor([ [1.0, 2.0, 3.0], [4.0, float('nan'), float('nan')], ], device=DEVICE) result = model_runner._get_nans_in_logits(logits) assert result == {"req_0": 0, "req_1": 2} result = model_runner._get_nans_in_logits(logits=None) assert result == {"req_0": 0, "req_1": 0} logits = torch.tensor([ [1.0, float('nan'), 3.0], ], device=DEVICE) result = model_runner._get_nans_in_logits(logits) assert result == {'req_0': 1, 'req_1': 0} logits = torch.tensor([ [float('nan'), float('nan'), 2.0], [1.0, 2.0, 3.0], [float('nan'), 2.0, 3.0], ], device=DEVICE) result = model_runner._get_nans_in_logits(logits) assert result == {'req_0': 2, 'req_1': 0} def test_update_states_no_changes(model_runner, dist_init): req_id = "req_0" # new req scheduler_output = _schedule_new_request(req_id) model_runner._update_states(scheduler_output) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) # schedule req scheduler_output = SchedulerOutput( scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData.make_empty(), num_scheduled_tokens={req_id: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids=set(), free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) metadata_before = model_runner.input_batch.sampling_metadata model_runner._update_states(scheduler_output) assert not _is_sampling_metadata_changed(model_runner, metadata_before) assert _is_req_added(model_runner, req_id) assert _is_req_scheduled(model_runner, req_id) assert _is_req_state_block_table_match(model_runner, req_id) def test_update_states_request_unscheduled(model_runner, dist_init): req_ids = ("req_0", "req_1") # new reqs scheduler_output = _schedule_new_request(*req_ids) model_runner._update_states(scheduler_output) assert _is_req_added(model_runner, req_ids[0]) assert _is_req_scheduled(model_runner, req_ids[0]) assert _is_req_added(model_runner, req_ids[1]) assert _is_req_scheduled(model_runner, req_ids[1]) # unschedule req_1 scheduler_output = SchedulerOutput( scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData.make_empty(), num_scheduled_tokens={req_ids[0]: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=0, finished_req_ids=set(), free_encoder_input_ids=[], structured_output_request_ids={}, grammar_bitmask=None, ) metadata_before = model_runner._update_states(scheduler_output) assert _is_sampling_metadata_changed(model_runner, metadata_before) assert _is_req_added(model_runner, req_ids[0]) assert _is_req_scheduled(model_runner, req_ids[0]) assert _is_req_added(model_runner, req_ids[1]) assert not _is_req_scheduled(model_runner, req_ids[1]) def test_kv_cache_stride_order(monkeypatch, model_runner): # This test checks if GPUModelRunner initializes correctly when an attention # backend enforces a non-default KV cache stride order. n_heads = model_runner.model_config.get_num_kv_heads( model_runner.parallel_config) expected_kv_cache_shape = [ 2, NUM_BLOCKS, BLOCK_SIZE, n_heads, model_runner.model_config.get_head_size() ] # TODO mla test default_stride = list(range(5)) # Permutation that gets you back to expected kv shape rnd_stride = tuple(random.sample(default_stride, len(default_stride))) def rnd_stride_order(): return rnd_stride # Patch the attention backend class and re-trigger the KV cache creation. for attn_backend in model_runner.attn_backends: monkeypatch.setattr(attn_backend, "get_kv_cache_stride_order", rnd_stride_order) model_runner.attn_backends = [] model_runner.attn_metadata_builders = [] model_runner.initialize_kv_cache(model_runner.kv_cache_config) # Shape is unchanged, but layout may differ kv_cache_shape = model_runner.kv_caches[0].shape assert list(kv_cache_shape) == expected_kv_cache_shape if default_stride == rnd_stride: assert all(kv.is_contiguous() for kv in model_runner.kv_caches) else: assert all(not kv.is_contiguous() for kv in model_runner.kv_caches) def test_load_model_weights_inplace(dist_init, model_runner, model_runner_2): # In this test, model_runner loads model + weights in one go, while # model_runner_2 loads dummy weights first then load real weights inplace model_runner.load_model() original_load_format = model_runner_2.load_config.load_format model_runner_2.load_config.load_format = "dummy" model_runner_2.load_model() # Initial model loading with dummy weights assert str(model_runner.get_model().state_dict()) != str( model_runner_2.get_model().state_dict()) model_runner_2.load_config.load_format = original_load_format model_runner_2.load_model() # Load real weights inplace assert str(model_runner.get_model().state_dict()) == str( model_runner_2.get_model().state_dict()) def test_init_kv_cache_with_kv_sharing_invalid_target_layer_order(): layer_0 = "model.layers.0.self_attn.attn" layer_1 = "model.layers.1.self_attn.attn" error_msg = f"{layer_1} must come before the current layer" with pytest.raises(ValueError, match=error_msg): fwd_context = { # initialization below will fail because target layer is invalid; # the target layer needs to come before layer 1 layer_0: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_0, kv_sharing_target_layer_name=layer_1, ), layer_1: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_1, ) } # suppress var not used error assert fwd_context is not None def test_init_kv_cache_with_kv_sharing_target_layer_not_exist(): layer_0 = "model.layers.0.self_attn.attn" layer_1 = "model.layers.1.self_attn.attn" invalid_layer = "model.layers.0.cross_attn.attn" error_msg = f"{invalid_layer} is not a valid Attention layer in the model" with pytest.raises(ValueError, match=error_msg): fwd_context = { layer_0: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_0, ), layer_1: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_1, # invalid layer: cross_attn.atn doesn't exist! kv_sharing_target_layer_name=invalid_layer, ) } # suppress var not used error assert fwd_context is not None def test_init_kv_cache_with_kv_sharing_target_same_as_current(): layer_0 = "model.layers.0.self_attn.attn" layer_1 = "model.layers.1.self_attn.attn" error_msg = f"{layer_1} cannot be the same as the current layer" with pytest.raises(ValueError, match=error_msg): fwd_context = { # initialization below will fail because target layer is invalid; # the target layer needs to come before layer 1 layer_0: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_0, ), layer_1: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_1, kv_sharing_target_layer_name=layer_1, ) } # suppress var not used error assert fwd_context is not None def test_init_kv_cache_without_kv_sharing(): layer_0 = "model.layers.0.self_attn.attn" layer_1 = "model.layers.1.self_attn.attn" vllm_config = get_vllm_config() with set_current_vllm_config(vllm_config): fwd_context = { layer_0: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_0, ), layer_1: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_1, ) } # suppress var not used error assert fwd_context is not None # Set high context length to test max context length estimation vllm_config.model_config.max_model_len = 3_000_000 vllm_ctx = vllm_config.compilation_config.static_forward_context runner = GPUModelRunner(vllm_config, DEVICE) kv_cache_spec = runner.get_kv_cache_spec() assert len(kv_cache_spec) == 2 assert len(runner.shared_kv_cache_layers) == 0 available_memory = 20 * GiB_bytes # page size for layer 0's kv_cache_spec is 32KB num_expected_blocks = 327680 # 20GB / 32KB / 2 (num layers) kv_cache_config = get_kv_cache_config(vllm_config, kv_cache_spec, available_memory) assert kv_cache_config.num_blocks == num_expected_blocks assert len(kv_cache_config.kv_cache_tensors) == 2 assert kv_cache_config.kv_cache_tensors[0].size == available_memory // 2 assert kv_cache_config.kv_cache_tensors[1].size == available_memory // 2 max_context_len =\ estimate_max_model_len(vllm_config, kv_cache_spec, 5 * GiB_bytes) # max context len with KV sharing should be 2x as large as without assert max_context_len == 1310720 # important: override tensor size to prevent large mem alloc during test # this will only allocate 2 block worth of memory (2 * 32kb) kv_cache_config.num_blocks = 1 for kv_cache_tensor in kv_cache_config.kv_cache_tensors: kv_cache_tensor.size = ( kv_cache_spec[kv_cache_tensor.shared_by[0]].page_size_bytes) runner.initialize_kv_cache(kv_cache_config) layer_0_kv = vllm_ctx[layer_0].kv_cache[0] layer_1_kv = vllm_ctx[layer_1].kv_cache[0] # check layer 1 kv cache does NOT share memory with layer 0 assert id(layer_1_kv) != id(layer_0_kv) # check layer 1 added to kv cache group's layer names assert len(kv_cache_config.kv_cache_groups) == 1 assert len(kv_cache_config.kv_cache_groups[0].layer_names) == 2 assert kv_cache_config.kv_cache_groups[0].layer_names[0] == layer_0 assert kv_cache_config.kv_cache_groups[0].layer_names[1] == layer_1 def test_init_kv_cache_with_kv_sharing_valid(): layer_0 = "model.layers.0.self_attn.attn" layer_1 = "model.layers.1.self_attn.attn" vllm_config = get_vllm_config() with set_current_vllm_config(vllm_config): fwd_context = { layer_0: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_0, ), layer_1: Attention( num_heads=8, head_size=64, scale=1.0, prefix=layer_1, kv_sharing_target_layer_name="model.layers.0.self_attn.attn", ) } # suppress var not used error assert fwd_context is not None # Set high context length to test max context length estimation vllm_config.model_config.max_model_len = 3_000_000 vllm_ctx = vllm_config.compilation_config.static_forward_context runner = GPUModelRunner(vllm_config, DEVICE) kv_cache_spec = runner.get_kv_cache_spec() assert len(kv_cache_spec) == 1 assert layer_0 in kv_cache_spec assert runner.shared_kv_cache_layers[layer_1] == layer_0 available_memory = 20 * GiB_bytes # page size for layer 0's kv_cache_spec is 32KB # with KV sharing, we can allocate (available_mem//page_size//1) blocks # which is twice as many as without KV sharing num_expected_blocks = 655360 # 20GB / 32KB kv_cache_config = get_kv_cache_config(vllm_config, kv_cache_spec, available_memory) assert kv_cache_config.num_blocks == num_expected_blocks assert len(kv_cache_config.kv_cache_tensors) == 1 # Each layer now has twice the available memory for KV cache # compared to no KV sharing assert kv_cache_config.kv_cache_tensors[0].size == available_memory max_context_len =\ estimate_max_model_len(vllm_config, kv_cache_spec, 5 * GiB_bytes) # max context len with KV sharing should be 2x as large as without assert max_context_len == 2 * 1310720 # important: override tensor size to prevent large mem alloc during test # this will only allocate 1 block worth of memory (32kb) kv_cache_config.num_blocks = 1 kv_cache_config.kv_cache_tensors[0].size =\ kv_cache_spec[layer_0].page_size_bytes runner.initialize_kv_cache(kv_cache_config) layer_0_kv = vllm_ctx[layer_0].kv_cache[0] layer_1_kv = vllm_ctx[layer_1].kv_cache[0] # check layer 1 kv cache shares memory with layer 0 assert id(layer_1_kv) == id(layer_0_kv) # check layer 1 added to kv cache group's layer names assert len(kv_cache_config.kv_cache_groups) == 1 assert len(kv_cache_config.kv_cache_groups[0].layer_names) == 2 assert kv_cache_config.kv_cache_groups[0].layer_names[0] == layer_0 assert kv_cache_config.kv_cache_groups[0].layer_names[1] == layer_1