Tiering/Caching

Flash vs. DRAM in PCs – Flash Wins

Chart from Objective Analysis report: How PC NAND will Undermine DRAMSome time ago Objective Analysis ran nearly 300 standard benchmarks on a PC with varying amounts of flash and DRAM and found that a dollar’s worth of flash provided a greater performance boost than a dollar’s worth of DRAM once the DRAM size grew above a certain minimum (1-2GB) depending on the benchmark.

You might wonder how this could possibly be true.  Everyone knows that best way to improve any computing system’s performance is to add DRAM main memory.  How could flash, which is orders of magnitude slower than DRAM, provide a bigger performance boost than DRAM?

It all makes sense if you think of the DRAM of something that is there only to make the HDD look faster.  More is better, but if you can use a little less DRAM and add a large flash memory layer then disk accesses appear to speed up even more.

The benchmark data and the price/performance findings that are Continue reading

IBM Software + SanDisk Hardware

One of SanDisk's InfiniFlash BoardsIn a joint press release, SanDisk and IBM announced support for each other’s products.  The IBM Spectrum Scale filesystem will support SanDisk’s InfiniFlash all-flash array to provide a high-capacity high-speed software-defined storage system.

At first glance this may seem a little odd, since IBM sells its own all-flash array, the FlashSystem, which became an IBM product line when the company acquired Texas Memory Systems (TMS) back in 2012.  That is not the case, though.  IBM has been validating that its Spectrum Storage products will work with just about any storage type that its customers may want to use.  Rather than narrowing this software’s support to only IBM storage systems, IBM is showing that Spectrum Scale is flexible enough to work with a multitude of solutions, supporting InfiniFlash the same as it does other internal server capacity and other external storage in the form of JBODs (“Just a Bunch of Disks”) or JBOFs (“Just a Bunch of Flash”).

In this case IBM has worked with SanDisk to validate that its Spectrum Scale storage management software works with InfiniFlash, just as it does with those many other storage solutions.

In the announcement IBM explains that Continue reading

IBM Adds Server-Side Caching

IBM's FlashCache Server-Side Caching SoftwareIBM today announced its FlashCache Storage Accelerator, a software product that supports flash caching in a broad range of systems.  FlashCache operates over three families of IBM servers (System x, BladeCenter and Flex System) and a variety of flash types to accelerate any back-end storage, including non-IBM storage arrays.

Although the cache’s data is dynamically updated to match the random workloads of virtualized systems (i.e. to accelerate VMware), it also improves the performance of Windows and Linux environments.

The cache uses a Write Through policy to solve a number of Continue reading

White Paper: Using Flash as Memory

DRAM, Flash, and HDD HierarchyToday NAND flash is being shoehorned into HDD formats simply because it is persistent – the data doesn’t disappear when the lights go out.  This approach fails to take advantage of NAND’s greatest strength – its low cost relative to DRAM – and this prevents it from fully meeting the needs of most data centers.

Since 2004 NAND has been cheaper than DRAM, and today its price per gigabyte is an order of magnitude lower than that of DRAM.  NAND is cheaper and slower than DRAM, and HDD is cheaper and slower than NAND.

A role better suited to NAND flash technology is Continue reading

Diablo: Flash Belongs on the Bus

Diablo TechnologiesDiablo Technology has just introduced a new set of DIMMs that put flash memory right onto the DDR3 memory bus.

I can already hear readers saying: “Wait!  You can’t do that!”  Well, you’re right, but the new module comes awfully close to that by putting the NAND behind an ASIC that interfaces between the DDR3 bus and the NAND.

Why do this?  Quite simply because you can get more “Bang for the Buck” by adding NAND to the system once you’ve reached a certain DRAM size.  The Diablo “Memory Channel Storage” (MCS) approach supports the addition of terabytes of NAND at the loss of Continue reading

OCZ Launches Database Accelerator

OCZ ZD-XL GraphicOCZ has just introduced a new software/hardware combination aimed at accelerating the performance of Microsoft SQL Server.  The OCZ ZD-XL SQL Accelerator combines a custom PCIe SSD with caching software optimized for the SQL Server workload.  The company boasted that this product won the “Best of Interop 2013” award, a distinction certainly worth crowing about!

How does this product differ from standard caching software?  OCZ tells us that the key elements required to Continue reading

Webinar: Flash Best Practices

I had the opportunity to participate in a round table webinar covering the best practices for solid state storage on July 18.  The hour-long session (including Q&A) can be replayed at BrightTalk.

In this round table webinar entitled Best Practices for Solid State Storage Implementation storage analyst Tom Coughlin moderated three of us, Radoslav Danilak of Skyera, Esther Spanjer of SMART Storage Solutions, and The SSD Guy (Yours Truly) in a Continue reading

SanDisk Upgrades FlashSoft Cache

SanDisk's FlashSoft Enterprise Caching SoftwareSanDisk has rolled out a new revision of its FlashSoft server-side enterprise caching software that includes multiple improvements over the prior versions.  The new release adds:

  • Support for multiple SSDs of mixed sizes and types
  • Concatenation of two or more SSDs into a single caching volume
  • SSD mirroring for “Safe Write-Back” caching
  • A maximum cache size increase from 1TB to 2TB
  • 2,048 accelerated objects can be stored in each cache, up from the earlier release’s 255

The company prides itself in the ease with which the software and a server-side SSD can be added to a system without otherwise changing its storage architecture.

With the “Safe Write Back” feature the FlashSoft software has been upgraded Continue reading

PC Caching Software is Not All the Same

NVELO Dataplex Benchmarks Consistently Outperform Intel iSRTThe folks at NVELO recently provided The SSD Guy with some benchmark data comparing their Dataplex software’s performance against the Intel iSRT caching software that is becoming prevalent among Ultrabooks.

For those unaware of these two technologies, they are both caching software that automatically maintains “Hot” data within a low-capacity SSD while leaving “Cold” data on the system HDD. The end result is that the PC performs as if it boasts a large SSD when, in truth, it uses Continue reading

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