VMware’s vStorage API for Array Integration (VAAI) is one of the most-important storage technology advances of the decade, allowing the VMware ESX to integrate and coordinate operations with supported enterprise storage arrays. After an explosion of initial support, however, VAAI implementation slowed. IBM was notably absent from the party, listing only partial support for a single product line for the better part of the year. But they’ve turned on the VAAI heat, releasing full support for the XIV and SVC and promising DS8000 in the near future.
VAAIing for Attention
For the complete updated VMware VAAI support matrix, see my post, VMware VAAI Storage Array Support in Plain English
Under vSphere 4.1, VAAI includes three “primitives”, or supported features:
- Full copy enables the hypervisor to direct the storage array to copy data without sending it all the way “up the stack”
- Block zeroing supports enhanced thin provisioning communication
- Hardware-assisted locking allows the hypervisor to more-efficiently share a SCSI LUN
IBM’s original VAAI support amounted only to the basic T10 zeroing support using the generic “vmw_vaaip_t10” plugin on the SVC and related Storwize V7000. This fell well short of the specialized three-primitive plugins offered by rivals like EMC and HDS.
IBM VAAI Support is Spreading
Far from being asleep at the wheel, IBM was busy creating a complete VAAI implementation that would be portable across a variety of storage platforms. XIV was the first beneficiary of this work, gaining full VAAI support and a listing in the VMware ESX HCL. This came in version 10.2.4 of the XIV software, released and approved in April of 2011. But insiders hinted something more was on the way.
Today, IBM announced that their “IBM_VAAIP_MODULE” plugin would support the SAN Volume Controller (SVC) and related Storwize V7000 as well. The array-side functionality will be added in version 6.2 of the software, which IBM promises to deliver in June of this year.
Now, at the IBM Storage Summit, I hear that this same code will enable the DS8000 to support all three VAAI primitives shortly. Once this is delivered, IBM’s key platforms (XIV, SVC, and DS8k) will all support VAAI, putting IBM on par with their competitors.
Stephen’s Stance
I am pleased to see IBM planning full VAAI support, since I feel this is absolutely key to future storage developments. I am further impressed that they developed a cross-platform VAAI codebase that could be deployed across such diverse architectures as XIV, SVC, and DS8k. Once this is released, IBM will finally be up to speed with their key competition.
I won’t recommend anything that’s not on the official VMware hardware compatibility list (HCL), and I’m glad to see that V7000 and XIV is now listed. It will take months DS8k to appear, though. By that time, vSphere 5 (with its rumored VAAI enhancements) will be here. Hopefully IBM will be out day-and-date with support.