High Performant Virtualizationwith OpenVZ

Nilesh Bairagi

Agenda

Available options in virtualizationOpenVZ introductionLimitationsOpenVZ featuresExperience of OpenVZ in private cloudQuestions

Full Virtualization (emulation)

Use OS as it isNeed Virtual Machine MonitorPerformance overheadLow density

Paravirtualization

Need VMMBetter performance than emulatorModified guest OS

OS Virtualization

Good in both Performance overhead and scalabilitySingle OS gives isolated environmentsDynamic resource management

OpenVZ

OS based - by modifying kernel, which enable to create and run multiple virtual private servers (VPS) on same host OSVPS are isolated from each other with very little process overhead (1 – 3%)Processes in VPS are scheduled on all CPUs of host (by default)

Limits in OpenVZ

Mandates similar kernel But allows multiple distributions

Limited VPN capabilitiesHost is single point of failure

OpenVZ features

Installation has very low system requirements Intel Celeron, Pentium II, Pentium III,

Pentium 4, Xeon or AMD Athlon CPU, 128MB RAM, 4G free space

Dynamic resource managementVPS – Own users & groups, process tree, ip, network & routing, firewall etc.VPS are efficient in utilizing resources, therefore can exceed than actual allocated resources

Features cont…

Creation of VPS in few secondsUse of templates enables to use pre-configured servers (template cache)Scaling

Private cloud with OpenVZ

Less number of physical servers (also reduce cost, space and subsequent maintenance)Capacity planning for HW With monitoring and trending

Resource management is dynamic, immediately becomes effective (no reboot) Using packages like vzctl

Wide range of parameters to config

User_beancounters

Complexity abstracted by v-swap enabled kernels

OpenVZ cloud

Resource Management

Disk, CPU and memory customization Mounting VPS on SSD (fast read/write) SANSharing host resources amongst CT is easyLive migration is easy with checkpointRedudant VPS cost only disk spaceReproducible infrastructure

Questions??