SSDs Need Controllers with More, NO! Less Power

More Power-Less PowerThe Storage Developer Conference in September gave a rare glimpse into two very different directions that SSD architectures are pursuing.  While some of the conference’s presentations touted SSDs with increasing processing power (Eideticom, NGD, Samsung, and ScaleFlux) other presentations advocated moving processing power out of the SSD and into the host server (Alibaba, CNEX, and Western Digital).

Why would either of these make sense?

A standard SSD has a very high internal bandwidth that encounters a bottleneck as data is forced through a narrower interface.  It’s easy to see that an SSD with 20+ NAND chips, each with an 8-bit interface, could access all 160 bits simultaneously.  Since there’s already a processor inside the  SSD, why not open it to external programming so that it can perform certain tasks within the SSD itself and harness all of that bandwidth?

Example tasks would include Continue reading “SSDs Need Controllers with More, NO! Less Power”

Getting the Most from Data Center SSDs

2017-09-19 Calypso Real World Workload TestMy friend and associate Eden Kim of Calypso Systems has published a new white paper on real workloads for SSDs.

This is the company that has helped the Storage Networking Industry Association (SNIA) to develop performance tests for SSDs that get past the issues that plague SSD users: Yes, it does well when it’s new, but how will an SSD perform after a year or two of service?

Calypso has recently published a new White Paper entitled: Datacenter Server Real World Workloads.  This document analyzes real-life datacenter server workloads and performance to provide important insight into how an SSD might perform in actual environments rather than in synthesized workloads.  It compares data center class SSDs against SAS HDDs to take a lot of the guessing out of issues about IOPS requirements, endurance needs, and so forth by comparing the measured activity over 24 hours of a 2,000-outlet retail chain web portal running SQL.

The tests in the paper represent a Continue reading “Getting the Most from Data Center SSDs”

3D XPoint Memory at the Storage Developer’s Conference

3D XPoint Report GraphicThis Sunday (Sept. 20, 2015) I will be presenting my company’s findings on the 3D XPoint memory that was introduced by Intel and Micron in July.  I will be speaking at the Storage Networking Industry Association (SNIA) Storage Developer Conference (SDC) Pre-Conference Primer.  You can click the name  to be taken to the agenda.

This won’t be the only talk about persistent memory technology at the conference.  Prior to my presentation storage consultants Tom Coughlin and Ed Grochowski will give an overview of advances in nonvolatile memories, and following my presentation will be two Intel talks.

Intel will be covering this new technology a lot during the conference.  Of a total of 120 presentations at the conference and pre-conference primer, Intel will be presenting nine, seven of which directly name persistent memory or nonvolatile memory in the title.  Other firms will also be talking about NVM: AgigA, Calypso, HP, Pure Storage, and SMART Modular.  Even Microsoft alludes to it in a couple of its presentation titles.  Persistent memory is a hot issue.

So, the question for readers of The SSD Guy blog is: “Will this do away with SSDs?”

This is a question that was Continue reading “3D XPoint Memory at the Storage Developer’s Conference”

Where does NVRAM Fit?

AGIGARAM DDR4 NVDIMM (Photo Courtesy of AgigA Tech)There’s been a lot of interest in NVRAM recently.  This technology has been lurking in the background for decades, and suddenly has become very popular.

What is NVRAM?  Quite simply, it’s DRAM or SRAM that has a back-up flash memory a small controller, and a battery or super-capacitor.  During operation the DRAM or SRAM is used in a system the same way that any DRAM or SRAM would be used.  When power is interrupted the controller moves all of the data from the DRAM or SRAM to the flash using the backup power from the battery or super-capacitor.  When power is restored, the controller moves the contents of the flash back into the SRAM or DRAM and the processor can resume operation where it left off.

In some ways it’s storage and in some ways it’s memory, so Continue reading “Where does NVRAM Fit?”

Webinar: How Many IOPS Do You Really Need?

How Many IOPS Webinar Cover SlideEarlier today Tom Coughlin and I presented a BrightTalk webinar in league with the Storage Networking Industry Association (SNIA) to discuss our joint report: How Many IOPS is Enough?

The report is based upon a survey that asked IT managers about their enterprise IOPS requirements.  The webinar gives a taste of the report’s contents, and explains the survey methodology.  During the course of the webinar and at the end Tom and I answered a number of listener questions relating to the content.

The presentation also includes a little plug for SNIA’s client IOPS survey which is being run by downloading a program called the Workload I/O Capture Program, or “WIOCP.”

A replay of this webinar is available on the BrightTalk website.

The presentation was well received by our audience.  Have a listen.

IBM to Invest $1B in Flash Promotion

The following is excerpted from an Objective Analysis Brief e-mailed to our clients on 15 April, 2013:

Comparison of 3-Year Operating Costs: Flash vs HDD (Wikibon)On April 11 IBM kicked off “The IBM Flash Ahead Initiative”, committing to spend more than $1 billion for flash systems and software R&D and to open twelve IBM Flash Centers of Competency around the world staffed with flash experts armed with flash systems to help clients test drive flash in their own situations.

This follows from IBM’s August 2012 agreement to acquire privately-held Texas Memory Systems (TMS), a very low profile manufacturer of high-performance flash-based memory arrays and PCIe SSDs. TMS is the world’s oldest SSD maker, founded in 1976, to manufacture RAM-based replicas of HDDs. About four years ago TMS used its Continue reading “IBM to Invest $1B in Flash Promotion”

Understanding Storage Delays

Jim PappasJim Pappas of Intel, a fellow member of SNIA (the Storage Networking Industry Association) shared a really intuitive way to understand storage delays at the last Storage Developer Conference (SDC).  It’s very simple.  First consider these two facts:

  • The difference between the speed of system memory and that of a hard disk drive (HDD) is roughly 6 orders of magnitude, or 1 million times
  • SSDs split the gap.  An SSD is about 1,000 times faster than an HDD, and is about 1,000 times slower than system memory.  Memory access times are measured in nanoseconds (ns), SSDs in microseconds (µs) and HDDs in milliseconds (ms)

The problem with understanding this (ns, µs, ms) is that Continue reading “Understanding Storage Delays”

SSDs and TCO

Shed some light on your SSD decisionOne of the best arguments to use an SSD is also one of the most difficult ways to sell anything.  This is the Total Cost of Ownership, commonly abbreviated to “TCO.”

TCO has been used as an argument for buying anything from compact fluorescent bulbs to Jaguar automobiles.

The argument usually revolves around an item whose initial price is higher, but which has lower ongoing (or operating) costs, and when these costs are combined, the higher-priced item proves to cost less to own over the long run.  In the case of a compact fluorescent (CF) bulb, the bulb may cost $7, versus $1 for an incandescent bulb, but it consumes 18 Watts compared to the 75 Watts consumed by the incandescent bulb it replaces.  In addition the CF bulb lasts ten times as long (10,000 hours vs. 1,000 hours.)  This works out to a savings of 470 kWh – or about $50 – plus $3 in bulb costs. Continue reading “SSDs and TCO”

New Booklet: How Controllers Maximize SSD Life

SNIA SSD Controller BookSNIA (The Storage Networking Industry Association) has conferred a great honor upon the SSD Guy by bringing all of the blog posts in the series How Controllers Maximize SSD Life into a single printed volume of the same name.

Readers can either ask for a print copy from SNIA, or can download a pdf rendition by visiting the SNIA SSSI (Solid State Storage Initiative) education web page.

How to Locate a Storage Bottleneck

Screenshot of the WIOCP in actionFew Sysadmins really understand what’s happening in the storage interface of their systems, yet there’s a lot of talk about SSDs with wide-ranging IOPS figures along with case studies of how these have helped solve system slowdowns.  The big question is: “How do you determine what your storage bottleneck is, and even whether or not one exists at all?”

Tom Coughlin and I discovered a very low level of understanding of this issue when we performed the IOPS survey late last year that we documented in our report: How Many IOPS do You Really Need?  A disconcerting number of respondents gave replies that Continue reading “How to Locate a Storage Bottleneck”