VMware has released a paper titled: “The CPU Scheduler in VMware vSphere 5.1“. The paper which contains 26 pages provides detailed explanations of ESXi CPU scheduling policies to help vSphere users who want to understand how virtual machines are scheduled.
The CPU scheduler is an essential component of vSphere 5.x. All workloads running in a virtual machine must be scheduled for execution and the CPU scheduler handles this task with policies that maintain fairness, throughput, responsiveness, and scalability of CPU resources.
The paper contains the following sections:
- Executive Summary
- CPU Scheduler Overview
- Proportional Share-Based Algorithm
- Relaxed Co-Scheduling
- Load Balancing
- Policy on Hyper-Threading
- NUMA Scheduling Policy
The ESXi CPU scheduler achieves fair distribution of compute resources among many virtual machines without compromising system throughput and responsiveness. Relaxed co-scheduling is a salient feature that enables both correct and efficient execution of guest instructions with low overhead. The ESXi CPU scheduler is highly scalable and supports very big systems and wide virtual machine.
vSphere 5.1 optimizes the load-balancing algorithm introduced in 5.0. It results in noticeable reductions in CPU scheduling overhead. A policy change on hyper-threaded systems enables out-of-the-box performance of 5.1 exceeding that of a tuned version of vSphere 4.1. No special tuning is required to achieve the best performance for most common application workloads. The irtual NUMA feature introduced in 5.0 can significantly improve performance of workloads that are optimized for a NUMA environment. With vNUMA, virtual machines of any size can display optimal performance on a NUMA system. The vNUMA feature is shown to significantly improve the performance of SPEC OMP workloads. Such improvement closes the performance gap between the virtual and the native environment for high-performance-computing (HPC) workloads.
blog comments powered by Disqus
virtualization.info Newest articles
July 19th, 2016
Yesterday IBM announced its results for Q2 2016.
If we compare with the same quarter in 2015 earnings per share, from continuing operations, decreased 22%. Net income, from continuing operations,…
June 24th, 2016
Red Hat announced its financial results for the first quarter of fiscal year 2017.
Total revenue for the first quarter was $568 million, with an increase of 18% from the…
June 24th, 2016
Today Red Hat released in beta version 4.0 of its KVM-based virtualization platform Red Hat Enterprise Virtualization (RHEV).
As a major release RHEV 4.0 ships a wide series of enhancements including:
June 21st, 2016
virtualization.info has been following WhatMatrix since its inception and, after 6 months since the website has been launched, we are happy to report that its community is growing and contributing…
June 21st, 2016
DockerCon 2016 began yesterday in Seattle with a number of announcements from Docker and key partners.
Here is a quick summary of the day:
Docker 1.12 with built-in orchestration: starting…
June 14th, 2016
Yesterday, Bellevue (WA) based company WinDocks, released a free edition of its homonymous port of the Docker daemon to Windows called WinDocks Community Edition.
The company, founded by a small…
May 12th, 2016
Containers’ security is one of the emerging topics in those companies moving this technology into production. A few small players emerged to compete exclusively in this portion of the…
May 3rd, 2016
RightScale is a Santa Barbara, CA based company, provider of a Software as a Service (SaaS) management solution that so far only supported standard Infrastructure as a Service (IaaS) cloud…
April 5th, 2016
Yesterday, Bellevue (WA) based company WinDocks, released version 1.0 of its homonymous Docker engine for Windows.
The company, founded by a small group of former Microsoft’s employees, rides Docker’s…
March 17th, 2016
LANDesk Software, founded in 1985 and headquartered in Salt Lake City, Utah , provides systems management, security management, service management, asset management and process management solutions with a strong focus…
March 15th, 2016
Last week open source giant Red Hat announced the availability of version 3.6 of its KVM-based virtualization platform Red Hat Enterprise Virtualization (RHEV).
While this new release provides the expected…
March 4th, 2016
Yesterday Docker announced to have acquired a semi-stealth startup called Conductant, focused on workloads orchestration.
Both Conductant’s founders, Bill Farner and David Chung, have significant enterprise experience coming from…
March 1st, 2016
Today Cisco announced the intent to acquire CliQr Technologies Inc., a privately held company based in San Jose, CA.
CliQr is one of the most promising startups in the Cloud…
February 11th, 2016
Yesterday VMware announced version 7 of both its vCloud and vRealize suites, confirming its efforts to be relevant in the CMPs (Cloud Management Platforms) space.
vRealize Suite 7 is made…