[Bugfix] fix cpu offload hang with tp=1 (#5963)

### What this PR does / why we need it?
As issue #5948 reported，when using cpu_offload_connector with TP=1, the
server will hang on starting, we found several bugs here to fix.
1. some crash error encountered because of code changed with vllm
version updating, some of them can be fixed as #5948, and this PR fixed
all of them.
2. hang problem described in #5948, the direct reason is that in
cpu_offload_connector, RPC client using the same client id in scheduler
and worker when tensor_parrallel_size is 1, this PR force the client id
to be different, then it is fixed.

- Why we didn't find this hang problem before?
Because we using --distributed-executor-backend mp or
tensor_parrallel_size > 1 in our test, in our old test case, the
scheduler and workers are different procceses, then client ids build by
`worker-{os.getpid()}` are not the same. But when using
tensor_parrallel_size=1, vllm will use uniproc as
distributed-executor-backend by default, the scheduler and worker will
by in the same proccess, then client ids are the same and hang.

### Does this PR introduce _any_ user-facing change?

### How was this patch tested?

- vLLM version: v0.13.0
- vLLM main:
2c24bc6996

Signed-off-by: lidenghui <lidenghui1110@gmail.com>

vllm_ascend/distributed/kv_transfer/kv_pool/cpu_offload/cpu_kv_cache_manager.py

@@ -5,12 +5,11 @@ from typing import Optional
 from vllm.logger import logger
 from vllm.utils.hashing import sha256
 from vllm.v1.core.block_pool import BlockPool
-from vllm.v1.core.kv_cache_utils import (BlockHash, KVCacheBlock,
+from vllm.v1.core.kv_cache_utils import (BlockHash, KVCacheBlock)
-                                         PrefixCachingMetrics)
 from vllm.v1.core.single_type_kv_cache_manager import \
     get_manager_for_kv_cache_spec
 from vllm.v1.kv_cache_interface import KVCacheSpec
-from vllm.v1.metrics.stats import PrefixCacheStats
+from vllm.v1.metrics.stats import (PrefixCacheStats, CachingMetrics)
 from vllm.v1.request import Request
 
 
@@ -20,7 +19,7 @@ class CPUCacheStats:
         self.enable_prefix_caching = enable_prefix_caching
         self.log_stats = log_stats
         self.prefix_cache_stats = PrefixCacheStats() if log_stats else None
-        self.cpu_prefix_cache_metrics = PrefixCachingMetrics()
+        self.cpu_prefix_cache_metrics = CachingMetrics()
         self.time_sec = int(time.time())
 
     def log(self):
@@ -111,6 +110,7 @@ class CPUKVCacheManager:
             block_pool=self.block_pool,
             kv_cache_spec=self.single_type_manager.kv_cache_spec,
             use_eagle=self.use_eagle,
+            alignment_tokens=self.block_size,
         )
         num_computed_tokens = len(computed_blocks[0]) * self.block_size
         self.req_to_computed_blocks[request_id] = computed_blocks[0]

vllm_ascend/distributed/kv_transfer/kv_pool/cpu_offload/cpu_offload_connector.py

@@ -75,7 +75,8 @@ class CPUOffloadingConnector(KVConnectorBase_V1):
     def __init__(self,
                  vllm_config: VllmConfig,
                  role: KVConnectorRole,
-                 kv_cache_config: Optional[KVCacheConfig] = None):
+                 kv_cache_config: Optional["KVCacheConfig"] = None):
+        self._connector_metadata = CPUOffloadingConnectorMetadata(requests={}, finished_req_ids=set())
         if not vllm_config.cache_config.enable_prefix_caching:
             self.connector_scheduler: Optional[
                 CPUOffloadingConnectorScheduler] = None

vllm_ascend/distributed/kv_transfer/kv_pool/cpu_offload/metadata.py

@@ -45,7 +45,9 @@ class MetadataServer:
 
     class ZMQRPCClient:
 
-        def __init__(self, identity=f"worker-{os.getpid()}"):
+        def __init__(self, identity=None):
+            if identity is None:
+                identity = f"worker-{os.getpid()}-{id(self)}"
             logger.info(f"metadata client for worker {identity} started")
             self.ctx = zmq.Context()  # type: ignore
             self.socket = make_zmq_socket(