WhipTail Technologies has introduced a solid-state storage appliance that
allows solution providers to maximize data throughput, solves disk contention issues
and simplify storage management for customers.
In a $48 billion storage market that analysts say is growing about 14
percent a year, solution providers are always looking for ways to increase
their customers’ efficiency and utilization rates and lower costs, says Ed
Rebholz, CEO of WhipTail.
For midmarket and enterprise customers, Rebholz says, a major problem has
been the fact that server processor speed has far outpaced the speed of storage
networks and appliances, creating a bottleneck in the data center.
“What ends up happening is organizations deploy high-performance servers
that end up being starved for data,” Rebholz says. “The storage infrastructure
hasn’t been able to keep up with the servers.”
What that lag time creates is a situation where organizations have problems
accessing data stored from mission-critical applications like Exchange, SAP
and other business applications, says Rebholz. Normally, solution providers
have addressed these problems simply by throwing more disk arrays at customers’
data centers, which can be costly and difficult to manage.
“Traditionally, solution providers would just add more disks to the array,
but that occupies data center space, it increases power consumption [and]
cooling costs, and it’s hard to manage all those devices,” says James
Candelaria, WhipTail’s CTO. And with so many
drives spinning at 15,000 RPM, disk failure
is always a concern, he adds.
The newly launched WhipTail appliance uses NAND flash and solid-state drive
(SSD) technology combined with proprietary
software to deliver enterprise-class storage performance at consumer prices,
says Candelaria.
Using consumer-grade MLC SSDs, Candelaria says, WhipTail’s solution
providers can replace more than two racks of Fibre Channel storage with a
single appliance that costs about the same as high-end solutions from EMC,
Network Appliance or Hitachi Data Systems, for instance.
“We can use the MLC-grade disks and have them outperform the
enterprise-class SLC drives because of the software stack,” he says. “And we
can replace as many as 30 arrays with one appliance.”
And while NAND flash is nonvolatile and has low power requirements and
excellent read performance, there is a drawback, says Candelaria. NAND flash
has poor random write performance—as much as 10 to 15 times worse than
traditional disks, if data’s written to it randomly, he says.
To circumvent this, WhipTail’s software allows data to be written to the
disks sequentially to boost write performance and reduce wear on the
disks. The data is written to a buffer that’s sized depending on the size
of the underlying flash and can scale from about 48MB to over 100MB, according
to Candelaria.
When the buffer’s full or the data exceeds a preset age, it’s flushed to
archival storage on the back end, and the process starts again, he says.
The WhipTail solution is a perfect fit for solution providers whose
customers need faster OLTP (online transaction processing), messaging,
virtualization or database access, Candelaria says, since these applications
are incredibly intensive.
“Because so much of the processing is random in these applications, the
system has to wait until the data spins around on the disk and shows up before
it can pull it up,” he says. But by using sequential writes and reads,
intelligent buffering and linearization—which allows forward writes on drives
instead of traditional random, back-and-forth writes—WhipTail can increase
application performance and decrease wear on drives, Candelaria says.
He adds that messaging, especially Exchange and IBM’s
Lotus, are also processor-intensive and can benefit from the addition of a
WhipTail appliance to a customer’s infrastructure.
“Messaging applications average one I/O per second per user, and that’s just
for storage,” Candelaria says. “Until now, the only way to support a
traditional Exchange deployment was to throw more spindles at it, and we’d see
customers with up to 300 spindles. We can support up to 10,000 users with just
one appliance.”
And while WhipTail’s appliance will set solution providers back about
$60,000 for a 1.5TB appliance, Candelaria says the lifespan of the appliance
far exceeds that of traditional storage arrays.
A constant defragmentation process ensures there’s a minimum amount of free
space on the appliance, he says, and assembles partial blocks of data into full
blocks to conserve storage space. While this process does put a little bit of
wear on the flash, because of the sequential write patterns and the linear
arrangement of data, WhipTail can expect to far exceed the typical seven-year
life cycle of a storage array, he says.
“Even if you write to the array every day, customers might only average 20
percent writes a day, so really, technically this could last 35 years,” he
says, more than enough time to get a huge return on investment.
“But we like to be pessimistic,” Candelaria adds.
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