Enterprise SSDs

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

Storage Visions Conference Coming Oct 22

Once again The SSD Guy will be playing a part in the annual Storage Visions conference which has been moved this year to the Santa Clara Hyatt Hotel adjacent to the Santa Clara Convention Center.  It’s now a 2-day conference (October 22-23) and has an agenda packed with interesting subjects, speakers, and panelists.

Storage Visions’ mission is to bring together the vendors, end users, researchers and visionaries that will meet growing demand for digital storage for the “coming data tsunami.”

I will moderate a panel on an exciting new technology that is currently known by a few different names, including “In-Situ Processing,” “Computational Storage,” and “Intelligent SSDs” (iSSD).  It’s a kind of SSD that uses internal processing to reduce the amount of data traffic between the server and storage.  This helps get past an issue that plagues many applications which spend more time and energy moving data back and forth than they do actually processing that data.

The panel, at 8:15 Monday morning, October 22, is Continue reading

Podcast: Flash Memory Summit

GreybeardsThose of you who enjoy listening to podcasts may want to hear Ray Lucchesi (Silverton Consulting) and Howard Marks (Deep Storage) interview me for their series “Greybeards on Storage.”

This interview is their 70th episode covering the world of storage.  These guys do a fantastic job of probing this industry with great enthusiasm and insight.

This episode is a 42-minute compendium of the sights and goings-on at last August’s Flash Memory Summit along with a number of side trips into the world of SSDs and memory chips.  It’s not strictly structured, and not strictly serious, but just three industry insiders having a lot of fun sharing their observations.

Some of the broad range of subjects that we Continue reading

The Micron QLC SSD – No Surprises Here

Progression of SSDsLast Monday, May 21, Micron introduced the industry’s first QLC SSD for enterprise applications.  Micron’s press release is HERE.

Although this is a laudatory feat, the industry has been headed in this direction for a number of years.  In fact, this was the subject of a presentation that I made to the Storage Networking Industry Association (SNIA) during its Winter Symposium in January 2014.

The slide in which I discussed this appears as this post’s graphic.  (Click on it to see a larger rendition.)  This table attempted to illustrate that all SSDs were headed towards TLC (and implicitly QLC) over the long term despite the fact that naysayers persistently argued that this could never happen.  It looks at attitudes over history and considers the fact that things that the industry said could “Never” happen ended up eventually becoming the mainstream technology.

Since I live, eat, and breathe Continue reading

NVDIMM Report Now Available

I am proud to share the release of a new Objective Analysis report detailing the nonvolatile dual inline memory module (NVDIMM) market.  Titled: “Profiting from the NVDIMM Market,” this report explains the What, How, Why, & When of NVDIMMs, and forecasts the market through 2021.

Readers are aware that I have been watching this market for some time, and never really know whether I should post about NVDIMMs in The SSD Guy or in The Memory Guy, since the boundary between memory and storage is bridged by these products.  My solution: publish posts about this report in both blogs!

According to the Objective Analysis NVDIMM market model the NVDIMM market can be expected to reach nearly 12 million units by 2021, representing a 105% average annual growth rate.  The forecast methodology used for this model has provided some of the semiconductor business’ most consistently-accurate forecasts.  The report, which includes this forecast, was the result of thorough research into the technology and the circumstances that led to the introduction of NVDIMMs, NVDIMM vendor and user interviews, and briefings from those standards bodies that are diligently working to provide timely support for this new technology.

This in-depth 80-page analysis explores the Continue reading

Comparing SSDs to Tomatoes

TomatoA few years ago The SSD Guy posted an analogy that Intel’s Jim Pappas uses to illustrate the latency differences between DRAM, an SSD, and an HDD.  If we look at DRAM latency to be a single heartbeat, then what happens when we scale that timing up to represent SSDs and HDDs?  How many heartbeats would it take to access either one, and what could you do in that time?

I still think it’s a pretty interesting way to make all these latency differences easier to understand.

Just recently I learned of a Rich Report video of a 2015 presentation in which Micron’s Ryan Baxter uses a different and equally interesting analogy based on tomatoes.

Tomatoes aren’t the first thing that comes to my mind when I think about SSDs, but this video may change my way of thinking!

The tomato slide, 9:30 into the presentation, is Continue reading

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

IBM Aligns Itself with High Speed NVMe-based Storage

NVMe LogoIBM has announced that it is developing Non-Volatile Memory Express (NVMe) solutions to provide significantly lower latency storage.

NVMe is an interface protocol designed to replace the established SAS and SATA interfaces that are currently used for hard drives and SSDs. Coupled with the PCIe hardware backplane, NVMe uses parallelism and high queue depths to significantly reduce delays caused by data bottlenecks and move higher volumes of data within existing flash storage systems.

IBM has set itself to the task of optimizing the entire storage hierarchy, from the applications software to flash storage hardware, and is re-tooling the end-to-end storage stack to support NVMe. The company recognized years ago that both hardware and software would need to be redesigned to satisfy the needs of ultra-low latency data processing.

The company last year released products with Continue reading

Comparing Wear Figures on SSDs

DWPD TBW GB/Day TriangleI have been receiving questions lately from people who are puzzled when companies use different parameters than their competitors use to specify the endurance of their SSDs.  How do you compare one against the other?  Some companies even switch from one parameter to another to define the endurance of different SSDs within their product line.

I have found that Intel uses three different endurance measures for its products: DWPD (drive writes per day), TBW (terabytes written), and GB/day.

There’s not any real difference between any of these measures – each one is one way of stating how many times each of the SSD’s locations can be overwritten before the drive has gone past its warrantied life.

The relationships between these three measures are illustrated in this post’s graphic.  You can click on it to see an expanded version.  It’s all pretty simple.  We’ll spell out the relationships in detail below, but in brief, if you want to compare Continue reading

NGD’s 24TB SSD Is Just The First Step

NGD LogoWith the tagline: “Bringing intelligence to storage” start-up NGD Systems, formerly known as NexGen Data, has announced a 24 terabyte SSD that the company claims to be the highest-capacity PCIe/NVMe device available.

The read-optimized Catalina SSD employs a lot of proprietary NGD technology: Variable rate LDPC error correction, unique DSP (digital signal processing) algorithms, and an “Elastic” flash transition layer (FTL), all embodied in an NGD-proprietary controller.  This proprietary technology allows Catalina to offer enterprise performance and reliability while using TLC flash and less DRAM than other designs.

NGD claims that the product is already shipping and is being qualified by major OEMs.

Based on some of the company’s presentations at past years’ Flash Memory Summits the controller has been carefully balanced to optimize cost, throughput, and heat.  This last is a bigger problem than most folks would imagine.  At the 2013 Hot Chips conference a former Violin Memory engineering manager told the audience Continue reading