December 2, 2008 - Sven Huisman
VMware introduces View Composer: EMC not happy?
Today VMware introduced a name change and a new product suite. VMware View and VMware vCenter <old product name>. A lot of bloggers already reported this news, so I won’t go into this a lot. Just pick on of the following to read all about it:
What’s more interesting is that VMware View Manager 3 together with VMware View Composer is released.VMware View Composer is the technology also used in VMware Lab Manager, excuse me, VMware vCenter Lab Manager that enables the use of linked-clones or golden master image. This means that an administrator can install a virtual machine with a desktop OS and use that image to deploy other virtual desktops. It works like this:
- Create a snapshot of the golden desktop VM
- Use VMware View Manager to create a new pool of desktop VMs
- A replica is created of this snapshot. The newly created VMs will have a pointer to this replica and only the changes (delta’s) will be written to a delta-vmdk
- Quickprep takes care of PC name and domain-membership
Because the diskfile’s of the virtual desktops only contains the delta’s written to disk, these vmdk’s are a lot smaller. You can have hundreds, maybe thousands of virtual desktops, with only a fraction of the actual diskspace used. I don’t know what this does to your I/O performance but the linked-clones are attached to a replica, not directly to the golden desktop image. So you can have multiple replica’s to spread the load.
In the title of my post I questioned if EMC is happy with View Composer. Of course, EMC will not directly notice a drop in selling storage, but this “new” technology has great potential for the future. Imagine that you (can) use this technology for all your virtual machines, not just your virtual desktops. Together with “Thin provisioning” (enables the use of thin disks, vmdk’s that are not pre-allocated. Available with next release of VMware ESX or through commandline in ESX 3.5) this will save a lot of diskspace on your expensive storage. And we all know that 80% of our data is not activly used so that can be stored on cheaper storage :-).
BTW: Currently, Thin provisioning can not be used together with a View Composer image.