Overcommit is harmful because it encourages, and provides a wrong but plausible argument for, writing bad software.

Why do we overcommit memory?

Memory is overcommitted when the combined working memory footprint of all virtual machines exceed that of the host memory sizes. Because of the memory management techniques the ESXi host uses, your virtual machines can use more virtual RAM than there is physical RAM available on the host.

What is overcommit handling?

From Wikipedia, the free encyclopedia. Memory overcommitment is a concept in computing that covers the assignment of more memory to virtual computing devices (or processes) than the physical machine they are hosted, or running on, actually has.