diff --git a/examples/openclaw-plugin/memory-ranking.ts b/examples/openclaw-plugin/memory-ranking.ts
index 3e7b615df..33ef56954 100644
--- a/examples/openclaw-plugin/memory-ranking.ts
+++ b/examples/openclaw-plugin/memory-ranking.ts
@@ -222,6 +222,7 @@ export function pickMemoriesForInjection(
   items: FindResultItem[],
   limit: number,
   queryText: string,
+  scoreThreshold: number = 0,
 ): FindResultItem[] {
   if (items.length === 0 || limit <= 0) {
     return [];
@@ -254,6 +255,12 @@ export function pickMemoriesForInjection(
     if (used.has(item.uri)) {
       continue;
     }
+    // Respect score threshold when supplementing leaf memories with
+    // non-leaf items. Without this check, low-scoring memories bypass
+    // the threshold configured in recallScoreThreshold (see #1106).
+    if (clampScore(item.score) < scoreThreshold) {
+      continue;
+    }
     picked.push(item);
   }
   return picked;
diff --git a/openviking/session/compressor.py b/openviking/session/compressor.py
index 46b56ed41..f4e77a7f3 100644
--- a/openviking/session/compressor.py
+++ b/openviking/session/compressor.py
@@ -249,6 +249,16 @@ async def _merge_into_existing(
             target_memory.set_vectorize(Vectorize(text=payload.content))
             await self._index_memory(target_memory, ctx, change_type="modified")
             return True
+        except FileNotFoundError:
+            logger.warning(
+                "Target memory %s no longer exists — removing orphaned reference", target_memory.uri
+            )
+            # Clean up vector record for the missing file so it's not retried
+            try:
+                await self.vikingdb.delete_uris(ctx, [target_memory.uri])
+            except Exception:
+                pass
+            return False
         except Exception as e:
             logger.error(f"Failed to merge memory {target_memory.uri}: {e}")
             return False
diff --git a/openviking/utils/process_lock.py b/openviking/utils/process_lock.py
index 77a5d7d56..88e2955c3 100644
--- a/openviking/utils/process_lock.py
+++ b/openviking/utils/process_lock.py
@@ -37,26 +37,37 @@ def _is_pid_alive(pid: int) -> bool:
         return False
     try:
         os.kill(pid, 0)
-        return True
     except ProcessLookupError:
         return False
     except PermissionError:
         # Process exists but we can't signal it.
-        return True
+        pass
     except (OSError, SystemError):
         if sys.platform == "win32":
-            # On Windows, os.kill(pid, 0) raises OSError for stale or invalid
-            # PIDs instead of ProcessLookupError. In some environments it can
-            # also bubble up as SystemError from the underlying Win32 wrapper.
-            # Common failures include:
-            # - WinError 87 "The parameter is incorrect"
-            # - WinError 11 "An attempt was made to load a program with an
-            #   incorrect format"
-            # Treat these as "not alive" so stale lock files are correctly
-            # reclaimed on Windows.
             return False
         raise
 
+    # PID exists, but on Linux PIDs are recycled. Verify this is actually
+    # an OpenViking process by checking /proc/{pid}/cmdline to avoid false
+    # positives from PID reuse (see issue #1088).
+    if sys.platform.startswith("linux"):
+        try:
+            with open(f"/proc/{pid}/cmdline", "rb") as f:
+                cmdline = f.read().decode("utf-8", errors="replace").lower()
+            if "openviking" not in cmdline and "openviking-server" not in cmdline:
+                logger.info(
+                    "PID %d is alive but not an OpenViking process (cmdline: %.100s). "
+                    "Assuming stale lock from recycled PID.",
+                    pid,
+                    cmdline[:100],
+                )
+                return False
+        except OSError:
+            # /proc not available or process exited between kill and open
+            pass
+
+    return True
+
 
 def acquire_data_dir_lock(data_dir: str) -> str:
     """Acquire an advisory PID lock on *data_dir*.