Latest ESXi Turns Off Transparent Page Sharing, So Watch Your RAM
Transparent Page Sharing is a technology from VMware that essentially deduplicates memory. Instead of having 100 copies of the same memory segment it keeps just one, and returns the savings to the user in the form of additional free capacity. In a move that further encourages people to never patch their systems VMware has set the new default for Transparent Page Sharing to “off.” They did this in the latest Updates to ESXi (ESXi 5.5 Update 2d, for example). More specifically, in order to use it by default you now need to configure your virtual machines to have a “salt,” and only VMs with identical salts will share pages. To specify a salt you need to manually edit a virtual …