1. TECHNICAL BULLETIN / COFFEE BREAK
SOLID STATE DISKS AND
STORAGE TIERING
A NEW DISK TIER
Standard hard disk drives (HDDs) are spinning disks, and their mechanical
actions can create a delay in data retrieval. Solid-state disks (SSDs) are an
exciting improvement in disk technology - made of silicon memory chips and
with no moving parts, SSDs have no rotational delay and near zero seek time,
dramatically reducing response times. SSDs can be extremely valuable to
applications that need fast performance.
SSDs offer a high-performance storage tier commonly
referred to as Tier 0. If storage administrators know
The solid-state disk market
of data that will be in high demand, they can place it
on SSD for fast performance, and place other data on
is growing as automated
HDD tiers. Since the effectiveness of SSD as a disk tier storage tiering takes hold, but
is based solely on how well the administrator can place it remains difficult for IT to
data, it remains a solution that is useful for IT shops with determine which applications
a known performance problem on specific data sets. can benefit from SSD tiers.
Most IT organizations are still unsure of whether SSDs
can help them cost effectively.
THE NEXT EVOLUTION: AUTOMATIC TIERING
Recently, however, storage vendors have begun offering automated tiering along
with better storage controller integration. Arrays can use SSDs dynamically,
in concept like a dramatically larger cache. Instead of fully populating an
enclosure with SSD drives, only a
few SSDs are included; intelligent
load-balancing algorithms identify
“hot” data sets and move them to
the SSD tier. When the data sets are . . . And then
Solid State Disk
no longer “hot,” they are moved back Hot data is returned to HDD
to a slower tier. Organizations can moved to SSD. . . when no longer
hot.
use fewer SSDs, and use them more
efficiently. This type of automated
deployment can spread SSD usage
across more data and applications,
Hard Disk Drives
eliminate the manual task of assigning
data to an SSD tier, and reduce costs.