OCZ: Three Solid State Storage Products in Three Weeks

OCZ's PCIe Z-DriveSSD maker OCZ has been on something of a tear recently, introducing three new solid state storage products in three weeks:

  • Two weeks ago the company introduced the Z-Drive R4 CloudServ PCIe SSD, designed for the data center, in single-card capacities ranging from 300GB-16TB.  This product can transfer data at multiple gigabytes per second rates to deliver over a million IOPS.
  • Last week saw the introduction of the OCZ-SANRAD VXL enterprise storage accelerator, after OCZ’s January acquisition of SANRAD.  This product is flash cache acceleration software for VMware ESX and Citrix Xen virtualized environments that allows Continue reading “OCZ: Three Solid State Storage Products in Three Weeks”

New White Paper: Enterprise Reliability, Solid State Speed

Kaminario's K2 SystemThe SSD Guy has just posted a new white paper to the Objective Analysis home page.  It’s about Kaminario‘s approach to solid state storage.

Yes, this is a commissioned white paper, but that doesn’t preclude my taking the same unbiased approach my clients have come to expect.  Kaminario has re-thought how SSDs should be used in storage, and that deserves some attention.

It’s only six pages, but even so I will condense the content for this post:  Flash is tricky Continue reading “New White Paper: Enterprise Reliability, Solid State Speed”

UCSD – Future SSDs Will Lack Performance

UCSD Chart Showing Write Latency Increases with Increasing SSD Capacity over TimeAt last week’s USENIX conference UCSD researcher Laura Grupp presented a paper that attracted a lot of attention.  The paper, which had a somewhat misleading title: The Bleak Future of NAND Flash Memory predicts that NAND-based SSDs of the future: “may be too slow and unreliable to be competitive against disks of similar cost in enterprise applications.”

Continue reading “UCSD – Future SSDs Will Lack Performance”

Fast New Intel SSD: The 520

Intel's 520 Press PictureIntel has announced a new SSD for the Enthusiast/Gamer market.  Intel’s fastest drive to date, this SSD, formerly known as “Cherryville” but now called the 520, is the first Intel SSD to use a SandForce/LSI controller and is made using Intel’s own 25nm flash.

Intel worked with SandForce for  a year and a half to produce an SSD that met Intel’s rigorous standards, and made hundreds of changes to SandForce’s firmware.  Users of SandForce controllers can differentiate their SSDs through the addition of features in the SSD controller’s firmware.  Intel did this by tapping into its expertise in end-to-end data protection (something the company learned when working with Hitachi to introduce that company’s Intel-based enterprise SSDs) while harnessing Intel’s deep understanding of its own NAND flash and of the I/O needs of the PC.

End-to-end data protection is not a trivial feature: Continue reading “Fast New Intel SSD: The 520”

Standards for SSD Endurance

The Grand Canyon - An Extreme Example of WearSSD endurance is an important concern that stands in the way of SSD adoption in a number of data centers.  Since flash is new to the enterprise (and computing systems are a new market for flash) important issues including wear specifications still need to be hammered out.

Until flash SSDs started experiencing adoption in standard computing environments, nobody really anticipated the difficulties that would arise from flash’s inherent wear-out mechanism.  Most flash manufacturers erroneously believed that Continue reading “Standards for SSD Endurance”

Fusion-io’s Billion IOPS Monster

Meter Showing Fusion-io's Billion IOPS PerformanceLast night (1/5/12) at a DEMO Enterprise event in San Francisco Fusion-io unveiled a one billion IOPS (I/Os per second) storage system.  A billion IOPS!

The machine was built using 64 Fusion-io ioDrive2 Duos connected to eight HP ProLiant DL370 servers.

This came sooner than we anticipated.  It was only in July 2008 that the million-IOPS barrier was broken by IBM using 41 Fusion-io devices.

Continue reading “Fusion-io’s Billion IOPS Monster”

SandForce: The Cloud needs Different SSDs

SandForceOn Monday December 13 SandForce introduced SSD controllers designed specifically for cloud computing applications.

You might wonder what is so different about cloud applications that they need an SSD controller of their own.  SandForce makes some interesting points:

  1. Cloud applications need low latency
  2. Cloud computing centers, like client SSDs, need a lot of capacity at a very low price Continue reading “SandForce: The Cloud needs Different SSDs”

New Seagate Hybrid Drives: 2x the Flash, 2x the I/O Speed

Seagate's Momentus XT Hybrid HDDSeagate has just announced an upgrade to the company’s Momentus XT hybrid HDD family.  Seagate announced in August that the company had already shipped over one million units of its first generation Momentus XT since its May 2010 introduction.

For those unaware of what a hybrid HDD is, the short answer is that it’s a way to get HDD capacities and SSD speeds at a price marginally higher than that of an HDD. Continue reading “New Seagate Hybrid Drives: 2x the Flash, 2x the I/O Speed”

SSD Garbage Collection

garbage cansOne of the thorniest issues in SSD design how to manage erasing blocks that are no longer in use.  That’s saying a lot, because NAND flash presents so very many difficult challenges like wear leveling, bad block management, error correction, and write amplification.

The difficulty stems from the fact that all of today’s software was written for HDDs which don’t behave like the flash in an SSD.  An HDD can over-write existing data with new data.  In a flash SSD, a block must be erased before being over-written and this can take a half a second – a huge amount of time in the world of computing.  Since the software doesn’t accommodate flash’s “erase-before-write” needs, the controller inside the SSD must take care of this bit of housekeeping.  Unused and unerased blocks are moved out of the way and erased in the background.  This is called the “garbage collection” process. Continue reading “SSD Garbage Collection”

Sometimes SSDs Don’t Improve System Speed

Slow, Slow, Slow!The SSD Guy attended TechTarget‘s Storage Decisions Conference last week in San Francisco.  Dennis Martin of Demartek gave a very good presentation called Making the Case for Solid-State Storage.

Demartek tests a lot of systems based on various forms of storage.

I really liked an expression that Mr. Martin shared to compare SSDs to HDDs.  He said that SSDs cost dollars per gigabyte and pennies per IOPS, while HDDs cost pennies per gigabyte and dollars per IOPS.  This is a really good way to think about the strengths and weaknesses of these two technologies.  There is every reason to use a mix of both. Continue reading “Sometimes SSDs Don’t Improve System Speed”