If you are looking for the reason and don't want to fight the system settings, these are two major situations I faced:
- You may have an infinite loop without next or recordest.movenext
- Your text data is very large but you think it is not! The common reason for this situation is to copy-paste an Image from Microsoft word directly into the editor and so the server translates the image to data objects and saves it in your text field. This can easily occupies the database resources and causes buffer problem when you call the data again.