Any idea to this problem?

Could someone explain to me what is causing attached problem.

May this be caused by the lack on space on my server?

I am experiencing this a lot lately.


Googling the error message produced a number of hits indicating that
it can be caused by running out of space, so yes it could be caused by

By the way, please cut and paste text if possible rather than posting
images, it is much easier for those attempting to help. If you had
looked in log/production.log (assuming you are in production mode)
then you should have seen the message.