[galaxy-user] Internal Server Error and slow to refresh History

Hi All, When I tried to download the filtered datasets from my History at Galaxy to my computer, I always got this error information:

"Internal Server Error

Galaxy was unable to sucessfully complete your request

An error occurred.

This may be an intermittent problem due to load or other unpredictable factors, reloading the page may address the problem.

The error has been logged to our team. If you want to contact us about this error, please reference the following

GURU MEDITATION: #8aa15caba14d4a3e85ce7ab069"

What is the cause for this problem? In addition, It takes about 3 to 5 minutes to refresh my Histories or to view different Histories. However, it is very quick to refresh "Saved Histories". Is it normal?

Thanks.

Best,

Jianguang