Tag Archives: DRS

VMware vSphere v5 and Storage DRS

By Greg Schulz, Server and StorageIO @storageio

Recently VMware announced version 5.0 of their vSphere virtualization solution with a theme of reducing complexity, enabling automation, and supporting scaling with confidence. As a key component for supporting cloud, virtual and dynamic infrastructure environments, vSphere V5.0 includes many storage related enhancements and new features. Continue reading VMware vSphere v5 and Storage DRS

Exploring a Limitation of VMware DRS

I have been a big fan of VMware’s Distributed Resource Scheduler (DRS). VMware DRS is a service or feature that will dynamically allocate and balance computing resources across the hosts in a cluster. In all of the environments I have work with so far, DRS has been a fantastic tool for getting and maintaining that balance across all the hosts in a cluster. Recently though I have come across a limitation of VMware’s DRS that is worth mentioning. Continue reading Exploring a Limitation of VMware DRS

Replacing DRS – With What and Why?

DRS is one of the most useful and interesting features of VMware vSphere (to be more specific – feature of versions of vSphere from Enterprise on up). DRS is useful because it prevents workloads (VM’s) that are consuming more than the expected amount of resources, from potentially harming the performance of their neighbors in the same host with this “excess” resource consumption. DRS is interesting because the idea of dynamically balancing the load of a system in order to ensure the performance of the critical workloads running on that system is something that was taken for granted in the days of the mainframe, but has not as yet been well implemented on distributed Intel architecture systems. Continue reading Replacing DRS – With What and Why?

vSphere 4.1 Improvements in Availability

With the release of vSphere 4.1 there have been some great enhancements that have been added with this release.  In one of my earlier post I took a look at the vSphere 4.1 release of ESXi.  This post I am going to take a look at vSphere 4.1 availability options and enhancements. So what has changed with this release?  A maximum of 320 virtual machines per host has been firmly set.  In vSphere 4.0 there were different VM/Host limitations for DRS as well as different rules for VMware HA. VMware has also raised the number of virtual machines that can be run in a single cluster from 1280 in 4.0 to 3000 in the vSphere 4.1 release. How do these improvements affect your upgrade planning? Continue reading vSphere 4.1 Improvements in Availability

Dynamic Resource Load Balancing

I just finished writing all the content for my next book entitled  VMware ESX and ESXi in the Enterprise: Planning Deployment of Virtualization Servers (2nd Edition) which continues the discussion on Dynamic Resource Load Balancing (DRLB). DRLB is the balancing of virtualized workloads across all hosts within a cluster of virtualization hosts without human intervention. This is the ultimate goal of automation with respect to virtualization and therefore the cloud. In effect, with DRLB the virtualization administrators job has been simplified to configuration and trouble shooting leaving the virtual environment to load balance work loads on its own.

This is a lofty goal, and we are not quite there yet, but we are further along than when I wrote VMware ESX Server in the Enterprise: Planning and Securing Virtualization Servers when ESX 3.0 first shipped. But what has really changed, as I talk to people, much of the automation is still done by hand coding specifics to all environments. I think we are close, and take some of the real innovations as writ and move on from there.

Continue reading Dynamic Resource Load Balancing

Managing the I/O Performance Aspects of Your Virtual Environment

Almost every enterprise that I have spoken to about their experiences in virtualizing anything more than simple or tactical applications has come across one or more that did not perform well once virtualized. In most cases these were applications that used low amounts of CPU and reasonable and predictable amounts of memory, so it stood to reason that resource conflicts in these areas were not the cause of the performance issues. Most of these enterprises had the network support for the virtualized hosts dramatically over-configured with multiple-teamed NIC’s and redundant HBA’s, so there was every reason to believe that the network was most likely not the issue either. Continue reading Managing the I/O Performance Aspects of Your Virtual Environment