The vStorage API for Array Integration (VAAI) program provides a mechanism for storage partners to integrate their array products with vSphere to achieve greater efficiencies and scalability. Storage vendors leveraging this API framework can deliver unique incremental capabilities in vSphere virtualized environments that other vendors cannot replicate. Customers benefit through increased vSphere scalabiity and improved virtual machine performance due to offloading storage operations to the array. Customers will also realize better cost efficiency in their storage arrays, because this integration allows virtual machines to utilize storage arrays more effectively.
This program validates partner-provided integration components that operate in conjunction with storage arrays listed on VMware’s Hardware Compatibility List.
Why Storage with the vStorage API for Array Integration is Better
Arrays integrated with vSphere through the vStorage API for Array Integration create significant advantages to the customer. These advantages can be relied on because they are built on a standard VMware interface, developed in cooperation with participating storage vendors. Customers can be assured that these features will continue to work for the long haul, and that VMware and our partners can effectively ensure quality through multiple product releases.
Integrated products also deliver the following performance advantages:
- Increased array scale and operational performance
- More effective utilization of storage arrays by virtual machines
Some storage array operations are inherently repetitive. There is little operational value in the traditional model in which the host issues a large number of identical commands in order to complete a this type of operation. By focusing on this class of commands and providing a specialized interface to offload the operation to the array processor with a single comprehensive instruction, host overhead drops dramatically, and array performance increases.
Increased array scale and operational performance: Arrays integrated with VAAI transparently offload certain storage operations to the array, while keeping the management interface intact. This significantly reduces CPU overhead on the vSphere host and consolidates activity on the array processor. Time to complete these operations is reduced, and the array is able to execute more useful work.
More effective utilization of storage arrays by virtual machines: VAAI integration enables three primary features to offload cycles from the host to the array. All qualified partners can leverage these.
- Full Copy. This command enables storage arrays to create a complete copy of data within the array without requiring traditional host read / write back sequences. This is useful in any large file duplication because it conserves storage I/O bandwidth, CPU and memory. However, it is extremely efficient for large-scale replication such as volume migration during Storage vMotion. Performance improves, system utilization is reduced, and operational flexibility is increased.
- Block Zeroing. This command directs storage arrays to zero out a large number of disk blocks as a simgle instruction. This feature will significantly accelerate provisioning of new virtual machines, especially when they require significant disk space. For multi-VM deployments, this can reduce critical-path time to availability.
- Hardware Assisted Locking. This command allows the array to take an active role in locking and unlocking a VMFS cluster file system. When the array ensures protection of the metadata for the file systems, the scalability of large vSphere server farms sharing a data store can be improved. Eliminating this constraint on scalability allows customers greater design flexibility to achieve higher server consolidation ratios, resulting in even greater operational efficiency.
Qualifying VAAI-integrated Arrays
Storage array vendors that can develop the necessary integration components for their array products can participate in the VAAI program.
The VMware Ready vStorage API for Array Integration Program is open to VMware Technology Alliance Partners enrolled at the Elite level. See the TAP program page for more information.
Qualified partners work with VMware to develop the firmware and plug-ins required by their arrays, with assistance from VMware as needed. This joint development effort is governed by a specific partner program agreement. Partners then use a VMware-supplied validation suite to ensure that their products conform to program standards.
