validation loop is too slow

[Wooho-Moon]

Thanks for awesomework!

I have a quick question.

I wonder why validation loop is too slow. I use 4 RTX3090 gpus. I find that when validation loop excute, GPUS isn't used. only one cpu core runs. Can you get me some advices for that issue?

Only 2 epoch is done during 10 hours... :(