ST1707

TECHNOLOGY: NVMe
NVME
NVMe: WHY THE FUSS?
NVMe IS BEING HERALDED AS THE KEY TO UNLOCKING THE FULL
POTENTIAL OF ALL-FLASH STORAGE, SAYS TOM O'NEILL,
INTERNATIONAL CTO, KAMINARIO - BUT THERE IS MORE TO A
SUCCESSFUL IMPLEMENTATION THAN JUST 'FORCING' NVME
DRIVES INTO YOUR EXISTING ENTERPRISE
Vendors across the storage and
network industries are rushing to
integrate the NVMe (non-volatile
memory express) protocol, regardless of
the costs attached, which can be quite
substantial.
NVMe technology, which has been around
since 2011, is the first protocol designed
specifically to handle non-volatile storage
devices. The protocol allows you to talk to
the storage medium more efficiently, with
higher levels of parallelism and lower
latency. Compared to the SAS and SATA
spinning disk-era protocols, NVMe is able
to handle a considerable increase in the
number of queues and of queue depth.
The NVMe protocol cuts down the latency
in the IO path by replacing the legacy SCSI
stack with a more modern and efficient one.
The NVMe protocol can also be used to talk
to storage devices across a network fabric
(this is described as NVMe-oF). What is
particularly useful is its ability to separate
the compute layer and the storage layer
while still operating at a very low latency.
This gives you a lot of options and
flexibility in the architecture, which is why
the industry is saying that NVMe will
modernise the data centre and bring in new
capabilities. But how do we ensure NVMe
and NVMe-oF integration is really worth it?
In the niche use cases of extreme
performance, cost and space efficiency
usually pose no real barriers (in these
instances, the new generation of tier-0
storage arrays may be a solution). The
compromises would include, for instance,
no data services, no data reduction, no
enterprise features and a very steep cost per
GB. For tier-0 workloads, where speeds and
feeds are the only really important metric,
these compromises may be acceptable.
DON'T FORCE IT
It's a different story for the enterprise:
products that are simply focused on forcing
NVMe drives into an existing array
architecture without thought of a use case
driven end-to-end architecture will not
benefit from this new technology. Such
architectures will incur 100% of the cost
side of the NVMe equation with only about
10% of the benefit side.
NVMe and NVMe-oF should be integrated
into a storage array without any
compromises. Furthermore, it must have a
clear path to a product that clearly
demonstrates real value-add for its
customers. In order to see the true value of
NVMe, next-generation storage technologies
must take advantage of NVMe drives at
scale, connected via NVMe over Fabrics to
create a truly agile storage platform.
A critical example of a capability that
NVMe-oF provide would be to dynamically
compose disaggregated resources in the
storage layer to lower operational complexity
and expenses, while at the same time
maintaining the data services which provide
the highest levels of performance, efficiency
and availability.
The real benefits of NVMe-oF and NVMe
will come when deployed together with faster
controllers and enterprise data services to
take full advantage of the new latency
advantages. Taken separately, the benefits
will be nominal latency improvements.
Imagine being able to completely decouple
storage controllers from capacity leveraging
advances in NVMe, NVMe fabric, and
NVMe network shelves. It would mark the
ultimate in cost-efficient, agile storage
infrastructure. Maintaining a highly
predictable infrastructure, IT organisations
would be able to optimise for cost,
performance and capacity. The data centre,
meanwhile, would scale infinitely.
More info: www.kaminario.com
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34 STORAGE July/August 2017
@STMagAndAwards
www.storagemagazine.co.uk
MAGAZINE