Memory reliability, also known as error insolation, allows ESXi to stop using parts of memory when it determines that a failure might occur, as well as when a failure did occur.

When enough corrected errors are reported at a particular address, ESXi stops using this address to prevent the corrected error from becoming an uncorrected error.

Memory reliability provides a better VMkernel reliability despite corrected and uncorrected errors in RAM. It also enables the system to avoid using memory pages that might contain errors.