Question about loss spike in training

<img width="1240" height="438" alt="Image" src="https://github.com/user-attachments/assets/f0551c6a-959b-4746-af4f-8901ff9e09b0" />
I'm training SIT-XL-2 with global bs = 1024 and bf16 and I meet this kind of loss spike. Is this a normal behaviour or some kind of errors?