When a computer goes into hibernation mode, it saves the contents of the RAM into the swap space so that it can resume exactly where it left off when it powers back on.
So, what if you are currently using more memory than you have RAM. In this case, some data that would otherwise be in RAM is saved to swap.
An example. A computer has 1GB of RAM and 1GB of swap space. It is currently using all but 100MB of RAM and 500MB of swap. Thus, it is needing to remember about 1.4GB of memory to save its state. However, swap is only 1GB.
What will happen in this case?
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As answered below, the hibernate fails. So then a follow-up question:
When this fails, where is the error reported?