Last week at VMWorld, IBM announced the Virtual Storage Optimizer (VSO), ESX-based software that reduces virtual desktop storage by creating a “golden image” of the desktop’s operating system and other static files, while saving the changes users might make to that image. It’s a concept akin to NetApp’s space-efficient snapshots, but because it’s delivered in software at the ESX level, IBM said, it can be applied to any storage system.
The next day, at a keynote, VMware officials demonstrated a new concept they’re rolling out in the next version of VMware Infrastructure called LinkedClones. LinkedClones create a “golden image” of virtual desktop files, as well as incremental changes;. The golden images, VMware demonstrated, can be updated with patches that automatically proliferate to all virtual machines based on the image to simplify rollouts and updates.
From the briefing I’d had with IBM the day before and this keynote demonstration, these products seemed similar. Since the VMware demo last Wednesday, I’ve been trying to assess what might be different about them. VMware officials I spoke with Wednesday and Thursday said they didn’t know enough about IBM’s product to comment on its differentiation and IBM spokespeople were unavailable. IBM’s press release about VSO had stated that it was “based on an algorithm developed by IBM Research,” but VMware said LinkedClones wasn’t based on anything from IBM.
Today I spoke with VMware director of enterprise desktop Jerry Chen, who told IBM’s VSO is based on the LinkedClones API. I asked about the algorithm developed by IBM. “There are things our partners can do to further optimize LinkedClone,” Chen said. “For example, there are different settings for the number of LinkedClones each master virtual machine can copy.”
Chen said he wasn’t familiar enough with the IBM product to say what VSO adds on top of LinkedClones. Meanwhile, IBM has been coy on this one. Since last week, I’ve put in numerous requests for comment by phone and email, including a fresh round of requests today after speaking with Chen. So far, no comments have been forthcoming.