VRA is software RAID, but Dot Hill Systems differentiates their product from previous software RAID products by increasing RAID reliability, performance and feature sets. For example, Dot-Hill claims that the performance of VRA rivals a RAID 0 due to how they have optimized their Universal RAIDCore Driver, taking advantage of less data handling and caching.
"When software RAID first showed up in Windows NT, the processors didn't have spare cycles to handle it. Today's processors available in SMB servers make software RAID viable. In addition, VRA's BIOS ROM option allow the server to boot from a RAID 5 partition, and is a welcome enhancement," Network Computing Contributing Editor and Chief Scientist at deepstorage.net Howard Marks said.
VRA also supports Touch Region Logging, which saves the regions to be written on a RAID 5 volume by the VRA to a table, prior to writing the data. Once the write is successful, the tabled is cleared. In the event of a power failure during a write, the VRA uses the Touch Region Logging feature to rebuild the drive more quickly.
VRA will be available through OEM and ORD vendors in two forms. First, there is an entry level bundle that supports basic RAID functions for levels 0, 1, 5, and 10. Them, through optional software licenses, advanced features like multi-vendor controller support, multiple arrays per drive, mixed capacity drives, split mirror, and Touched Region Logging will be available through a separate license available by end of the 2009.
The success of VRA is going to rely partly on the pricing model as well. Dot Hill expects the pricing to be under $10 for high volume OEM/ODM's for RAIDCore Basic with user upgrades starting between $50-$75. The pricing is a far cry from hardware RAID adapters run which start around $500 street price and doesn't come with the baggage that software RAID has. That price is low enough to compete with hardware RAID.