Information about Cloud Computing (IaaS) and VMware Technologies

This is really interesting and important question for the VMware professional. Who and when will host reclaim the memory, the answers follows: VMKernel is responsible for the reclaiming the memory. VMKernel decides to reclaim the host memory based on their four states. ESX maintains the four memory states: High @ 6% - No Action Soft @ 4% - Ballooning Hard @2% - Swapping + Ballooning Low @1% - Swapping ESX effectively supports 3 memory reclaim techniques such as: 1. Transparent Share Paging (TPS) 2. Ballooning 3. Host Swapping Now, the ESX will decide which memory reclaims technique to be used at when. However, TPS is enabled by default and continuously running in the ESX host, it is not considered. Let’s see the how memory state is calculated: Memory State % = Physical Memory – Service Console Memory When the memory state equals to high state (6%) or virtual machines use less than 94% of host memory, there won’t be any reclaim process invoked. When the memory state...