The Best OS Installation Is Minimal

This is post #4 in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” In this day & age of virtualization and clouds the best choice for an OS installation, be it a virtual machine template or a physical machine, is a minimal install. From there you can use a configuration management tool like Chef or Puppet to add exactly the packages you need for the host to perform its functions. Doing a minimal install has several advantages: A minimal installation doesn’t install a lot of content that will just sit there and consume disk space. As a result your template VMs will be really small, which leads to fast provisioning …

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Minimal Kickstart File for Red Hat Enterprise Linux 6, CentOS 6, Oracle Linux 6 Virtual Machines

This is a helper post in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” Here’s a minimal kickstart file for a virtual machine installation of RHEL 6, CentOS 6, or Oracle Linux 6. I use this in conjunction with tools like Puppet and Chef to do the rest of my system configuration. I provision 30 GB thin-provisioned disks to each VM, leaving the rest of it unallocated until needed. While this leads to a disk overcommitment situation that’s manageable, and a tradeoff to ensure more standardization and ease of administration & automation. I remove a number of packages that we don’t necessarily need on a virtual machine, either …

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Performance Tuning and Configuration Management Go Hand In Hand

This is post #3 in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” I’ve really become a fan of configuration management tools like Chef and Puppet. Those types of tools help keep my systems in sync, help enforce standards I set for my systems, and help me rapidly deploy new systems that look exactly like my existing systems. When I’m doing performance testing & tuning these aspects are helpful. It’s easy to deploy a new virtual machine that looks exactly like the production VMs you have. Tuning is all about making a lot of little changes and seeing what they do, so by building test systems from the …

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One Workload Per Virtual Machine

This is post #2 in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” Back when the computing world was built on bare metal we often tried to squeeze more than one workload on a physical machine. We did this to save money. Servers are expensive so we wanted to make the most of each one. What we didn’t account for was how complicated things could get. Applications fought with each other over system libraries and DLLs. Security was complicated. And, most relevant to this series, performance tuning became this multivariate dance involving resource limits and other arcane system witchcraft. In the end we saved a little money on …

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Uptime Is Not Something To Be Revered

Slashdot has a link to a tribute video to a Sun that was up continuously for 3737 days. That’s 10.23 years. It’s like a sequoia tree seeing the passage of civilization around it: My thoughts on this: The data center and infrastructure powering this machine was built in such a way as to keep this thing powered continuously for 10 years. Whoever built and ran that infrastructure was doing a good job. It’s a generalization but I bet there are very few cloud providers that can boast anything like that. That version of Sun Solaris is reliable enough to keep operating for years without disruption. Most OSes are, by the way, even Microsoft Windows. That particular hardware is reliable enough …

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OpenStack, Lock-In, Support Costs, and Open Source Free Lunches

Since I posted my missive about OpenStack not being our savior from lock-in or support costs I’ve had a number of comments and discussions about it. The discussions generally start from the point of view that I’m wrong. Let’s take a look at a few of these. Also, it might seem like I’m picking on Randy Bias and Greg Ferro a little here but Randy seems like a good guy, and Greg is a friend, so there’s no animosity. Just point/counterpoint. TL;DR version: OpenStack is cool but isn’t some magic tech that prints money, open source doesn’t mean you don’t have to pay someone to support a service built on it, customized open source and custom solutions using open source don’t …

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Cloud Isn't Really About Technology

If there was one concept about “the cloud” I wish more people understood it is that the cloud is not a technological revolution. Sure, a faster and more pervasive Internet helps, but we’ve had vendor-hosted applications for years. Virtualization has created better opportunities for server infrastructure, lowering barriers to entry and helping us squeeze blood out of things we once treated as rocks. But, despite being almost continuously conflated with “cloud,” it isn’t the cloud. Not by itself. The cloud is about people and about process. It’s about organizations deciding to talk to each other internally, to collaborate and solve problems together. Cloud is about opening the door to automation and security and scalability, asking computers to do what they …

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Statistics Rollups Are Evil

It’s pretty common for statistics-gathering software, like MRTG, Cacti, VMware vCenter, etc. to roll statistics up over time by averaging them. This helps save space, as well as cut down on the processing needed to look at & graph the data. The problem is that the process is lossy. These systems save disk, memory, and CPU by averaging the data over longer and longer time periods. Those averages remove spikes and make the data less and less representative of what actually happened on your system or network. It also makes it damn near useless for planning and troubleshooting. Let’s start with an example I drew up in Excel to simulate something like vCenter recording an application server’s CPU load every …

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Free Upgrade to 25 GB for Microsoft SkyDrive Users

I don’t know all the details, so it may not apply to everybody, but if you’re a SkyDrive user (or just have an account) you might be eligible for a free upgrade from 7 GB to 25 GB (I haven’t heard of anybody not being eligible, though). Log in to Click “Manage Storage” on the bottom of the left navigation column. Click the magic button to upgrade your SkyDrive Free plan from 7 to 25 GB. It is my understanding that this is a limited-time offer, so get on it. It takes about 20 seconds if you know your password. 🙂

My New Intro Slide For Cloud Presentations

I think I’m going to start using this slide in presentations on cloud computing. I’ll just cross out “Afghanistan Stability” and write “IT.” I particularly like the “insurgents” and “narcotics” sections. Seems about right.