Category : Virtual Machines

CPU Optimisation

CPU Scheduler The CPU Scheduler, as the name suggests, schedules the CPU.  It schedules the virtual CPUs on the VM (vCPUs) on the physical CPUs on the host (pCPUs). The CPU Scheduler enforces a proportional-share algorithm for CPU usage across all virtual machines and VMkernel processes on the ESXi host. It enables support for symmetric

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VMware Virtual Machine Memory Guide

Memory Virtualisation Basics When an operating system is installed directly onto the physical hardware in a non-virtualised environment, the operating system has direct access to the memory installed in the system and simple memory requests, or pages always have a 1:1 mapping to the physical RAM, meaning that if 4GB of RAM is installed, and

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Virtual Machine Memory Overhead

Windows virtual machines require more memory with each passing release and software demands on memory are becoming larger all the time.  In a vitual environment it is quite simple to increase the amount of virtual memory granted to a virtual machine, especially with features such as hot add.  The ability to dynamically increase the amount

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Understanding virtual machine memory

Memory in a virtualised environment is split up in three memory types. Virtual Memory – Allocates memory through a syscall to the operating system.  This runs at the application level in the same way on virtual machines as in physical machines Physical Memory – Runs at the OS level.  In simplistic terms it uses an

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Virtual Machine configuration and maximums

Virtual machines are made up of the following files. vmname.vmx – Config file vmname.vmdk – Describes charateristics vmname-flat.vmdk – (hidden by default) Contains the data vmname.nvram – VM BIOS vmname.log – log file vmware#.log – VMware log file vmname.vswp – Virtual machine swap file on the ESX(i) host vmname.vmsd – snapshot descriptor file Limits per

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