AutoBatch protect from negative batch sizes (#9048)

utils/autobatch.py

@@ -60,6 +60,9 @@ def autobatch(model, imgsz=640, fraction=0.9, batch_size=16):
         i = results.index(None)  # first fail index
         if b >= batch_sizes[i]:  # y intercept above failure point
             b = batch_sizes[max(i - 1, 0)]  # select prior safe point
+    if b < 1:  # zero or negative batch size
+        b = 16
+        LOGGER.warning(f'{prefix}WARNING: ⚠️ CUDA anomaly detected, recommend restart environment and retry command.')
 
     fraction = np.polyval(p, b) / t  # actual fraction predicted
     LOGGER.info(f'{prefix}Using batch-size {b} for {d} {t * fraction:.2f}G/{t:.2f}G ({fraction * 100:.0f}%) ✅')