Solid-State Storage Can Trump Traditional Drives on Cost

When does expensive solid-state storage become less expensive than cheaper
rotating disks? Advertising analytics firm Marketing Architects found the
crossover happened when its business intelligence reports were taking up to 4
hours to run.

That’s when solution provider Clear North proposed a solid-state storage
solution that would resolve the bottleneck in Marketing Architects’ CRM
and analytics solution.

The firm had added many fields to its CRM
application from Pivotal, and that had degraded the performance in terms of
running reports. Marketing Architects turned to its database vendor to ask for
help, but the best suggestion it had was to port it all to a new database, a
project that would take a year and cost the company millions of dollars.

“When it was really slow, it affected productivity,” says Pete Sperling, a
partner at Clear North. “Everybody in the company was using the application.
And they were using hardware to make it better.”

Sperling says that’s what led Clear North to look at the Marketing
Architects’ database and how many I/Os they were pushing.

"They had a lot of drives—maybe 15 72GB drives for the database and at
least another 15 for the log files,” he says. “Space wasn’t an issue, but
performance was still very poor.”

By switching to solid-state storage instead, Clear North believed it would
be able to increase the I/Os significantly and fix the performance issues. But
solid state is an expensive alternative and pretty much brand new for this type
of application.

To help ease the customer’s concern, Clear North and vendor Compellent
offered a guarantee—it would take the solution back and not charge for the
labor if the solid-state storage solution didn’t turn out to provide the kind
of performance boost the company required.

“The results were very impressive,” Sperling says. “Reports that had taken 4
hours were down to the 10- to 15-minute range.”

The new solution included five 146GB solid-state drives with 25,000 to 5,000
I/Os each. “If they would try to equal that I/O with regular fibre drives they
would need 140 drives,” Sperling says.

Clear North put together the following solution modeling for Marketing
Architects.

The cost of each solid-state drive was about $19,000, totaling about $95,000
for five drives. Enclosures for these drives totaled two at a total cost of
$12,000.  All together, the solution cost $107,000 to get the 25,000 I/Os.

To get the same in fibre drives, Clear North’s model showed that the company
would need to spend $135,000 just for the drives alone. Enclosures would
cost another $54,000 for a total solution cost of $189,000 just to do the same
number of I/Os.

“When you do the pricing from an I/O perspective, it’s not even close,” says
Sperling. “The story will only continue to get better on solid state because
pricing will continue to come down.”

Clear North relied on Compellent’s software to manage storage. For example,
data that is never going to be touched can be migrated down to SATA drives and
parked there.

The software also optimizes for memory space taken versus performance, says
Sperling. That means that data that is not accessed for three days is then
saved in the RAID 5.5 format, which takes up less space but performs more
slowly.

“So we get the best of both worlds,” Sperling says.