diff --git a/scripts/dispatcher.py b/scripts/dispatcher.py
index 3a6d21d..a7195d5 100644
--- a/scripts/dispatcher.py
+++ b/scripts/dispatcher.py
@@ -184,7 +184,9 @@ def video_duration_s(worker: dict, worker_src: str) -> float:
 def do_extract(job: sqlite3.Row, worker: dict) -> str:
     videos = json.loads(job["video_paths"])
     frames_dir = f"{worker['frames_dir']}/job_{job['id']}"
-    ssh(worker["ssh_alias"], f"mkdir -p {shlex.quote(frames_dir)}")
+    # Clean any frame_*.jpg from a prior run so count_frames reflects this extraction only
+    # (retries/restarts otherwise inflate frame_count with duplicates).
+    ssh(worker["ssh_alias"], f"mkdir -p {shlex.quote(frames_dir)} && rm -f {shlex.quote(frames_dir)}/frame_*.jpg")
     idx = 0
     total_frames_est = 0  # will be computed after each scp
     for v in videos:
@@ -243,7 +245,7 @@ def do_reconstruct(job: sqlite3.Row, worker: dict, frames_dir: str) -> tuple[str
     # .87 has 23 GB RAM, .84 has 62 GB. Keep effective frame count ~4k to stay safe.
     frame_count = job["frame_count"] or 0
     ram_gb = 23 if worker["host"] == "192.168.0.87" else 62
-    ram_budget_gb = ram_gb * 0.55
+    ram_budget_gb = ram_gb * 0.45  # leave headroom for model + OS + cuda pinned buffers
     stride = 1
     while frame_count * 3.15 / 1024 / stride > ram_budget_gb:
         stride += 1