[Core] Optimize block_manager_v2 vs block_manager_v1 (to make V2 default) (vllm-project#5602)

Author: alexm-redhat

benchmarks/benchmark_latency.py

@@ -46,6 +46,7 @@ def main(args: argparse.Namespace):
         load_format=args.load_format,
         distributed_executor_backend=args.distributed_executor_backend,
         otlp_traces_endpoint=args.otlp_traces_endpoint,
+        enable_prefix_caching=args.enable_prefix_caching,
     )
 
     sampling_params = SamplingParams(
@@ -220,6 +221,9 @@ def run_to_completion(profile_dir: Optional[str] = None):
         action='store_true',
         help='If True, the prefill requests can be chunked based on the '
         'max_num_batched_tokens')
+    parser.add_argument("--enable-prefix-caching",
+                        action='store_true',
+                        help="Enable automatic prefix caching")
     parser.add_argument('--use-v2-block-manager', action='store_true')
     parser.add_argument(
         "--ray-workers-use-nsight",

tests/conftest.py

@@ -474,7 +474,7 @@ def generate(
             req_sample_output_strs: List[str] = []
             for sample in req_output.outputs:
                 output_str = sample.text
-                output_ids = sample.token_ids
+                output_ids = list(sample.token_ids)
                 req_sample_output_ids.append(prompt_ids + output_ids)
                 req_sample_output_strs.append(prompt_str + output_str)
             outputs.append((req_sample_output_ids, req_sample_output_strs))

tests/core/block/test_block_table.py

@@ -373,8 +373,9 @@ def test_cow(block_size: int, sequence_len: int, append_len: int,
                                    block_size) - (sequence_len // block_size)
 
     original_block_table.allocate(token_ids=token_ids, device=Device.GPU)
-    original_block_ids = original_block_table.physical_block_ids
+    original_block_ids = original_block_table.physical_block_ids[:]
 
+    print("original_block_ids = {}".format(original_block_ids))
     forked_block_table = original_block_table.fork()
 
     # Expect no additional allocation (copy on _write_).
@@ -457,7 +458,7 @@ def test_cow_lookahead_simple(block_size: int, sequence_len: int,
 
     # Allocate lookahead slots.
     original_block_table.ensure_num_empty_slots(lookahead_slots)
-    original_block_ids = original_block_table.physical_block_ids
+    original_block_ids = original_block_table.physical_block_ids[:]
 
     forked_block_table = original_block_table.fork()
 

tests/core/block/test_cpu_gpu_block_allocator.py

@@ -8,8 +8,8 @@
 @pytest.mark.parametrize("num_gpu_blocks", [1024])
 @pytest.mark.parametrize("block_size", [16])
 @pytest.mark.parametrize("allocator_type", ["naive", "prefix_caching"])
-def test_allocate_mutable(num_cpu_blocks: int, num_gpu_blocks: int,
-                          block_size: int, allocator_type: str):
+def test_allocate_mutable_block(num_cpu_blocks: int, num_gpu_blocks: int,
+                                block_size: int, allocator_type: str):
     allocator = CpuGpuBlockAllocator.create(
         allocator_type=allocator_type,
         num_gpu_blocks=num_gpu_blocks,
@@ -21,14 +21,14 @@ def test_allocate_mutable(num_cpu_blocks: int, num_gpu_blocks: int,
     assert allocator.get_num_free_blocks(Device.GPU) == num_gpu_blocks
 
     cpu_blocks = [
-        allocator.allocate_mutable(prev_block=None, device=Device.CPU)
+        allocator.allocate_mutable_block(prev_block=None, device=Device.CPU)
         for _ in range(num_cpu_blocks)
     ]
     assert allocator.get_num_free_blocks(Device.CPU) == 0
     assert allocator.get_num_free_blocks(Device.GPU) == num_gpu_blocks
 
     gpu_blocks = [
-        allocator.allocate_mutable(prev_block=None, device=Device.GPU)
+        allocator.allocate_mutable_block(prev_block=None, device=Device.GPU)
         for _ in range(num_gpu_blocks)
     ]
     assert allocator.get_num_free_blocks(Device.CPU) == 0
@@ -47,8 +47,8 @@ def test_allocate_mutable(num_cpu_blocks: int, num_gpu_blocks: int,
 @pytest.mark.parametrize("num_gpu_blocks", [1024])
 @pytest.mark.parametrize("block_size", [2])
 @pytest.mark.parametrize("allocator_type", ["naive", "prefix_caching"])
-def test_allocate_immutable(num_cpu_blocks: int, num_gpu_blocks: int,
-                            block_size: int, allocator_type: str):
+def test_allocate_immutable_block(num_cpu_blocks: int, num_gpu_blocks: int,
+                                  block_size: int, allocator_type: str):
     allocator = CpuGpuBlockAllocator.create(
         allocator_type=allocator_type,
         num_gpu_blocks=num_gpu_blocks,
@@ -67,18 +67,18 @@ def test_allocate_immutable(num_cpu_blocks: int, num_gpu_blocks: int,
     assert allocator.get_num_free_blocks(Device.GPU) == num_gpu_blocks
 
     cpu_blocks = [
-        allocator.allocate_immutable(prev_block=None,
-                                     token_ids=token_ids,
-                                     device=Device.CPU)
+        allocator.allocate_immutable_block(prev_block=None,
+                                           token_ids=token_ids,
+                                           device=Device.CPU)
         for token_ids in cpu_token_ids
     ]
     assert allocator.get_num_free_blocks(Device.CPU) == 0
     assert allocator.get_num_free_blocks(Device.GPU) == num_gpu_blocks
 
     gpu_blocks = [
-        allocator.allocate_immutable(prev_block=None,
-                                     token_ids=token_ids,
-                                     device=Device.GPU)
+        allocator.allocate_immutable_block(prev_block=None,
+                                           token_ids=token_ids,
+                                           device=Device.GPU)
         for token_ids in gpu_token_ids
     ]
     assert allocator.get_num_free_blocks(Device.CPU) == 0

tests/core/block/test_naive_block.py

@@ -14,11 +14,11 @@ def create_allocate_lambda(allocate_type: str,
                                prev_block: Optional[Block],
                                token_ids: List[int]):
         if allocate_type == "immutable":
-            allocate_block = lambda: allocator.allocate_immutable(
+            allocate_block = lambda: allocator.allocate_immutable_block(
                 prev_block=prev_block, token_ids=token_ids)
         elif allocate_type == "mutable":
-            allocate_block = lambda: allocator.allocate_mutable(prev_block=
-                                                                prev_block)
+            allocate_block = lambda: allocator.allocate_mutable_block(
+                prev_block=prev_block)
         else:
             raise ValueError()
 

tests/core/block/test_prefix_caching_block.py

@@ -26,11 +26,10 @@ def test_first_block_has_correct_content_hash(seed: int, block_size: int,
         token_ids = list(range(num_to_fill))
         mock_allocator = MagicMock(spec=PrefixCachingBlockAllocator)
 
-        block_with_prev = PrefixCachingBlock(
-            prev_block=None,
-            token_ids=token_ids,
-            block_size=block_size,
-            prefix_caching_allocator=mock_allocator)
+        block_with_prev = PrefixCachingBlock(prev_block=None,
+                                             token_ids=token_ids,
+                                             block_size=block_size,
+                                             allocator=mock_allocator)
 
         if is_curr_block_full:
             # Expect hash since block is full.
@@ -71,7 +70,7 @@ def test_nth_block_has_correct_content_hash(seed: int, block_size: int,
             prev_block=previous_block,
             token_ids=token_ids,
             block_size=block_size,
-            prefix_caching_allocator=mock_allocator,
+            allocator=mock_allocator,
         )
 
         if is_curr_block_full and prev_block_has_hash:
@@ -138,7 +137,7 @@ def create_chain(block_size: int,
                 prev_block=prev_block,
                 token_ids=[],
                 block_size=block_size,
-                prefix_caching_allocator=allocator,
+                allocator=allocator,
             )
 
             tokens_to_append = token_ids[block_number *
@@ -159,11 +158,11 @@ def create_allocate_lambda(allocate_type: str, allocator: BlockAllocator,
                                prev_block: Optional[Block],
                                token_ids: List[int]):
         if allocate_type == "immutable":
-            allocate_block = lambda: allocator.allocate_immutable(
+            allocate_block = lambda: allocator.allocate_immutable_block(
                 prev_block=prev_block, token_ids=token_ids)
         elif allocate_type == "mutable":
-            allocate_block = lambda: allocator.allocate_mutable(prev_block=
-                                                                prev_block)
+            allocate_block = lambda: allocator.allocate_mutable_block(
+                prev_block=prev_block)
         else:
             raise ValueError()
 
@@ -233,12 +232,13 @@ def test_allocate_immutable_ooms_many_hash(num_blocks: int,
 
         # Expect allocation with unseen hash to fail.
         with pytest.raises(BlockAllocator.NoFreeBlocksError):
-            allocator.allocate_immutable(prev_block=chain[-1],
-                                         token_ids=list(range(block_size)))
+            allocator.allocate_immutable_block(prev_block=chain[-1],
+                                               token_ids=list(
+                                                   range(block_size)))
 
         # Expect mutable allocation to fail.
         with pytest.raises(BlockAllocator.NoFreeBlocksError):
-            allocator.allocate_mutable(prev_block=chain[-1])
+            allocator.allocate_mutable_block(prev_block=chain[-1])
 
         # Expect allocation of exact same chain to pass.
         second_chain = TestPrefixCachingBlockAllocator.create_immutable_chain(
@@ -270,7 +270,7 @@ def test_free_prevents_oom(num_blocks: int, block_size: int):
 
         # Expect mutable allocation to fail.
         with pytest.raises(BlockAllocator.NoFreeBlocksError):
-            allocator.allocate_mutable(prev_block=None)
+            allocator.allocate_mutable_block(prev_block=None)
 
         block_to_free = chain[-1]
 
@@ -280,11 +280,11 @@ def test_free_prevents_oom(num_blocks: int, block_size: int):
             allocator.free(block_to_free)
             assert block_to_free.block_id is None, i
 
-            new_block = allocator.allocate_mutable(prev_block=None)
+            new_block = allocator.allocate_mutable_block(prev_block=None)
             assert new_block.block_id == block_id, i
 
             with pytest.raises(BlockAllocator.NoFreeBlocksError):
-                allocator.allocate_mutable(prev_block=None)
+                allocator.allocate_mutable_block(prev_block=None)
 
             block_to_free = new_block
 
@@ -376,17 +376,13 @@ def test_get_common_computed_block_ids(num_blocks: int, block_size: int,
 
         # Create token ids that will exhaust all blocks.
         token_ids = list(range(num_blocks_to_consume * block_size))
-        blocks = list(range(num_blocks_to_consume))
 
         first_chain = TestPrefixCachingBlockAllocator.create_immutable_chain(
             block_size=block_size,
             token_ids=token_ids,
             allocator=allocator,
         )
 
-        # mark all blocks in first chain as computed
-        allocator.mark_blocks_as_computed(blocks)
-
         # After zero_point, second_chain's token_ids would be set -1, which
         # make it different from here comparing with first_chain
         zero_point = random.randint(1, len(token_ids) - 1)
@@ -424,15 +420,16 @@ def test_alloc_promotion(num_blocks: int, block_size: int, seed: int):
                                                 block_size=block_size)
         token_ids = list(range(block_size))
 
-        block = allocator.allocate_immutable(prev_block=None,
-                                             token_ids=token_ids)
+        block = allocator.allocate_immutable_block(prev_block=None,
+                                                   token_ids=token_ids)
 
         assert allocator._refcounter.get(block.block_id) == 1
-        m = allocator.allocate_mutable(prev_block=None)
+        m = allocator.allocate_mutable_block(prev_block=None)
 
         block_id = m.block_id
         for i in range(block_size):
             m.append_token_ids([i])
+
         # After block get promoted to immutable from mutable, if there is
         # already same content hash block, then it shall be released into
         # hashless_allocator
@@ -452,48 +449,79 @@ def test_eviction_alloc_mixed(num_blocks: int, block_size: int, seed: int):
 
         all_blocks_list = [i for i in range(num_blocks)]
         zero_ref = {i: 0 for i in range(num_blocks)}
+        one_ref = {i: 1 for i in range(num_blocks)}
         allocator = PrefixCachingBlockAllocator(num_blocks=num_blocks,
                                                 block_size=block_size)
         token_ids = list(range(num_blocks * block_size))
 
-        # now we have num_blocks free blocks in hashless allocator
-        # with internal tracking list _blocks _cached_blocks and evictor
-        # empty and block's ref shall be 0
+        # Verify initial/pre-alloc state
+
+        # Ensure all blocks are free inside hashless allocator
         assert list(allocator._hashless_allocator._free_block_indices
                     ) == all_blocks_list
-        assert len(allocator._blocks.keys()) == 0
+        # Ensure no tracked blocks
+        assert len(allocator._block_tracker.keys()) == num_blocks
+        for block_id in range(num_blocks):
+            assert not allocator._block_tracker[block_id].active
+        # Ensure no cached blocks
         assert len(allocator._cached_blocks.values()) == 0
+        # Ensure no evicted blocks
         assert len(allocator.evictor.free_table.keys()) == 0
+        # Ensure 0s ref counts for all blocks
         assert allocator._refcounter._refcounts == zero_ref
 
         # Allocate immutable chains with only one block residuled in
         new_block = []
         for i in range(num_blocks):
-            block = allocator.allocate_immutable(
+            block = allocator.allocate_immutable_block(
                 prev_block=None,
                 token_ids=token_ids[block_size * i:block_size * (i + 1)])
             new_block.append(block)
 
+        # Verify post-alloc state
+
+        # Ensure no blocks are free inside hashless allocator
+        assert (len(allocator._hashless_allocator._free_block_indices) == 0)
+        # Ensure all blocks are tracked
+        assert len(allocator._block_tracker.keys()) == num_blocks
+        for block_id in range(num_blocks):
+            assert allocator._block_tracker[block_id].active
+        # Ensure all blocks are cached (all promoted)
+        assert len(allocator._cached_blocks.values()) == num_blocks
+        # Ensure no evicted blocks
+        assert len(allocator.evictor.free_table.keys()) == 0
+        # Ensure 1s ref counts for all blocks
+        assert allocator._refcounter._refcounts == one_ref
+
         # Free all blocks, and now all blocks shall be in the evictor
-        # there shall be no tracking data left in _blocks
+        # there shall be no tracking data left in _block_tracker
         # all blocks shall be tracked in _cached_blocks
         # all blocks' ref shall be zero
         for block in new_block:
             allocator.free(block)
 
-        assert len(allocator._blocks.keys()) == 0
+        # Verify post-free state
+
+        # Ensure no tracked blocks
+        assert len(allocator._block_tracker.keys()) == num_blocks
+        for block_id in range(num_blocks):
+            assert not allocator._block_tracker[block_id].active
+        # Ensure no blocks in hashless allocator (all promoted)
         assert len(allocator._hashless_allocator._free_block_indices) == 0
+        # Ensure all blocks are cached
         assert list(allocator._cached_blocks.values()) == all_blocks_list
+        # Ensure all blocks are inside the evictor
         assert list(allocator.evictor.free_table.keys()) == all_blocks_list
+        # Ensure 0s refcounts
         assert allocator._refcounter._refcounts == zero_ref
 
         # Allocate a mutable block, and the first block shall be evicted
         # and set its content hash into None, ref to 1
-        mutable = allocator.allocate_mutable(prev_block=None)
+        mutable = allocator.allocate_mutable_block(prev_block=None)
 
         assert mutable.block_id == 0
         assert mutable.content_hash is None
-        assert 0 in allocator._blocks
+        assert allocator._block_tracker[0].active
         assert allocator._refcounter.get(0) == 1
         assert 0 not in allocator._cached_blocks
         assert 0 not in allocator.evictor
@@ -502,27 +530,27 @@ def test_eviction_alloc_mixed(num_blocks: int, block_size: int, seed: int):
         # hashless allocator
         allocator.free(mutable)
 
-        assert len(allocator._blocks.keys()) == 0
+        assert not allocator._block_tracker[0].active
         assert allocator._refcounter._refcounts == zero_ref
         assert 0 not in allocator._cached_blocks
         assert 0 not in allocator.evictor
         assert 0 in allocator._hashless_allocator._free_block_indices
 
-        # when allocate immutable with first block_size tokens, we
+        # When allocate immutable with first block_size tokens, we
         # shall get free block from hashless allocator, thus no block left
         # in hashless
-        block = allocator.allocate_immutable(prev_block=None,
-                                             token_ids=token_ids[:block_size])
+        block = allocator.allocate_immutable_block(
+            prev_block=None, token_ids=token_ids[:block_size])
 
         assert block.block_id == 0
         assert len(allocator._hashless_allocator._free_block_indices) == 0
-        assert 0 in allocator._blocks
+        assert allocator._block_tracker[0].active
         assert 0 in allocator._cached_blocks.values()
         assert allocator._refcounter.get(0) == 1
         assert 0 not in allocator.evictor
 
         # allocate mutable block again, it shall be popped from evictor
-        mutable = allocator.allocate_mutable(prev_block=None)
+        mutable = allocator.allocate_mutable_block(prev_block=None)
         assert len(allocator._hashless_allocator._free_block_indices) == 0
         assert mutable.block_id not in allocator.evictor.free_table
         assert allocator._refcounter.get(mutable.block_id) == 1
@@ -619,7 +647,7 @@ def create_immutable_chain(
             block_token_ids = token_ids[block_number *
                                         block_size:(block_number + 1) *
                                         block_size]
-            prev_block = allocator.allocate_immutable(
+            prev_block = allocator.allocate_immutable_block(
                 prev_block=prev_block, token_ids=block_token_ids)
             blocks.append(prev_block)
 

tests/spec_decode/test_batch_expansion.py

@@ -90,10 +90,10 @@ def test_create_single_target_seq_group_metadata(k: int):
 
     assert output.request_id == input_seq_group_metadata.request_id
     assert len(output.seq_data) == 1
-    assert output.seq_data[target_seq_id].get_prompt_token_ids(
-    ) == prompt_tokens
-    assert output.seq_data[target_seq_id].get_output_token_ids(
-    ) == prev_output_tokens + token_ids
+    assert output.seq_data[target_seq_id].get_prompt_token_ids() == tuple(
+        prompt_tokens)
+    assert output.seq_data[target_seq_id].get_output_token_ids() == tuple(
+        prev_output_tokens + token_ids)
 
     assert len(output.block_tables) == 1
     assert output.block_tables[