Fix: start_training yield count (9), plt.close memory leak

app.py

@@ -15,11 +15,13 @@ GRPO_DIR     = '/app/runs/grpo'
 
 # ── Training process ────────────────────────────────────────────────────────────
 
+_NO_PLOT = [gr.update()] * 8  # 8 plot slots (reward,loss,fmt,diff,eplen,pie,tasks,stats)
+
 def start_training(model_choice, epochs, num_gen, hf_token):
     global _proc
     with _lock:
         if _proc and _proc.poll() is None:
-            yield gr.update(), gr.update(), gr.update(), "Already running."
+            yield gr.update(value="Already running."), *_NO_PLOT
             return
 
         env = os.environ.copy()
@@ -45,8 +47,7 @@ def start_training(model_choice, epochs, num_gen, hf_token):
     output = ''
     for line in _proc.stdout:
         output += line
-        # Yield log update every line; plots auto-refresh via Timer
-        yield gr.update(value=output), gr.update(), gr.update(), gr.update()
+        yield gr.update(value=output), *_NO_PLOT
 
     _proc.wait()
     output += f"\n{'='*60}\nDone (exit {_proc.returncode})"
@@ -445,16 +446,11 @@ def plot_ep_lengths(m):
     return fig
 
 def build_plots():
-    m = _load_metrics()
-    if m is None:
-        m = {}
+    plt.close('all')  # close all open figures before creating new ones
+    m = _load_metrics() or {}
     return (plot_reward_curve(m), plot_loss_curve(m), plot_format_rate(m),
-        plot_diff_curves(m), plot_ep_lengths(m),
-        plot_decision_dist(m), plot_task_scores(m), plot_stats_panel(m))
-
-
-def refresh_plots():
-    return build_plots()
+            plot_diff_curves(m), plot_ep_lengths(m),
+            plot_decision_dist(m), plot_task_scores(m), plot_stats_panel(m))
 
 
 # ── UI ───────────────────────────────────────────────────────────────────────────
@@ -560,7 +556,7 @@ with gr.Blocks(title='AP Commander Training', theme=gr.themes.Base()) as demo:
     start_btn.click(
         fn=start_training,
         inputs=[model_dd, epochs_sl, numgen_sl, hf_token],
-        outputs=[logs, plot_reward, plot_loss, plot_fmt, plot_diff, plot_eplen, plot_pie, plot_tasks],
+        outputs=[logs, plot_reward, plot_loss, plot_fmt, plot_diff, plot_eplen, plot_pie, plot_tasks, plot_stats],
     )
 
     eval_btn.click(