One of the enhancements or features in VMware’s latest release, vSphere, is the option to create virtual machines with thin provisioned disks. I found the skinny on Thin Provisioning with vSphere on the VMware Blog by Michael Adams.

vStorage Thin Provisioning optimizes storage costs through the most efficient use of storage in virtual environments. Storage requests more often than not are usually overestimated by users mostly to avoid having to go through the request/approval process. With vStorage Thin Provisioning, IT departments can now assure business users of storage space availability while deferring the actual costs of purchasing storage to when it is really needed. Full reporting and alerting on allocation and consumption ensure that virtual machines don’t really run out of storage, Storage VMotion and Volume Grow ensure that virtual machines can either migrate to datastores with additional storage or volumes can be increased in size when consumption approaches allocation.

Sounds pretty cool and can be a real cost saver.  This was the topic of conversation on this week’s VMTN Community Roundtable.  In case you missed it you, can hear the podcast from this link or you can also download from iTunes.  

Storage providers have been able to provide thin provisioning for awhile now and this has worked really well.  So now with vSphere we have a choice of where we want to handle thin provisioning. vSphere also makes it really easy to convert thick vmdk files to thin using Storage vMotion.   So which one should you use?  Well that is the real question.  Now, truth be told, I have only set up thin provisioning in my lab environment.  I am not sure if today I would try to make the selling point to switch from storage thin provisioning to VMware provisioning.  I guess I am under the belief that it might be better to leave this type of provisioning and control with the storage group.  I really have nothing to back that belief up one way or another it just seems to be the most logical choice. I do think that changing a process that is already in place might causes issues later. What happens if both VMware and the storage device both work to deliver thin provisioning at the same time?  I do not have the equipment in my lab to test but I really have to wonder.  Has anyone out there tried this? 

Now on the flip side of the coin, if the storage device is not providing thin provisioning then it would make good sense to take advantage of this technology by letting VMware handle this for you.  The next question would be, is thin provisioning for everything? Should it be used for some virtual machines and not others?  For me, personally, I am not ready to push new technology into production without taking some baby steps first. I think thin disks will work great for VDI and can greatly increase deployment times of the desktops.  I think that would be my first step and would not even consider the technology for mission critical application for at least a bit while my comfort and confidence level increases.

Aren’t these the steps that most companies follow when adapting new features or new technology?  I have no doubt that thin provisioning in one way or another will become the de facto standard as we move forward in time. Now what say you?  What are your thoughts on thin provision and how it should be handled?

ESX, Provisioning, virtualization, vmware

This entry was posted on Thursday, October 29th, 2009 at 9:29 am and is filed under vWire. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.