Knowledge Base

After installing ESX 4.0 or ESX 4.0 Update 1 on a server with more than 190GB of physical memory, booting the ESX host fails and opens the recovery shell due to a lesser amount of low reserved-memory (low-memory), and displays the following message in the VMkernel log:
module heap [Module heap name]: creation failed - Out of memory

This issue occurs when the low reserved-memory is around 2GB and the system has a large physical memory (around 190 GB).

ESX reserves a fraction of the low-memory for critical allocations. If the ESX host has a low amount of reserved physical memory, ESX might not have enough memory for all the non-critical low-memory requests while booting the host. In this scenario, the ESX host enters the recovery shell.