Understanding Flash: The Fall and Rise of Flash Memory

This month sees the four year anniversary of some interesting events. Commonwealth countries around the world celebrated the Diamond Jubilee of Queen Elizabeth II. Whitney Houston was tragically found dead in a Beverly Hills hotel. The Caribbean was hit hard by sargassum seaweed invasion. And I made the decision to leave the comfort of Oracle databases and join the exciting … Continue reading Understanding Flash: The Fall and Rise of Flash Memory →

Understanding Flash: What is 3D NAND?

3D NAND stacks flash cells vertically rather than shrinking them further, overcoming the physical limits of 2D planar NAND. This article explains how V-NAND and charge trap flash work and why they matter for enterprise storage.

All Flash Arrays: Hybrid Means Compromise

Sometimes the transition between two technologies is long and complicated. It may be that the original technology is so well established that it's entrenched in people's minds as simply "the way things are" - inertia, you might say. It could be that there is more than one form of the new technology to choose from, … Continue reading All Flash Arrays: Hybrid Means Compromise →

Why Kaminario?

This summer I made the decision to leave my previous employer and join another vendor in the All Flash Array space - a company called Kaminario. A lot of people have been in touch to ask me about this, so I thought I'd answer the question here... Why Kaminario? To answer the question, we first need to … Continue reading Why Kaminario? →

All Flash Arrays: SSD-based versus Ground-Up Design

In recent articles in this series I've been looking at the architectural choices for building All Flash Arrays (AFAs). I surmised that there are three main approaches: Hybrid Flash Arrays SSD-based All Flash Arrays Ground-Up All Flash Arrays (which from here on I'll refer to as Custom Flash Module arrays or CFM arrays) I've already blown metaphorical raspberries at … Continue reading All Flash Arrays: SSD-based versus Ground-Up Design →

All Flash Arrays: Where’s My Capacity? Effective, Usable and Raw Explained

What's the most important attribute to consider when you want to buy a new storage system? More critical than performance, more interesting than power and cooling requirements, maybe even more important than price? Whether it's an enterprise-class All Flash Array, a new drive for your laptop or just a USB flash key, the first question … Continue reading All Flash Arrays: Where’s My Capacity? Effective, Usable and Raw Explained →

All Flash Arrays: Can’t I Just Stick Some SSDs In My Disk Array?

In the previous post of this series I outlined three basic categories of All Flash Array (AFA): the hybrid AFA, the SSD-based AFA and the ground-up AFA. This post addresses the first one and is therefore aimed at answering one of the questions I hear most often: why can't I just stick a bunch of SSDs … Continue reading All Flash Arrays: Can’t I Just Stick Some SSDs In My Disk Array? →

Understanding Flash: Summary – NAND Flash Is A Royal Pain In The …

NAND flash is a genuinely difficult storage medium – it wears out, has slow erases, and requires complex management. This article summarises the Understanding Flash series and explains why architecture is what separates great all-flash arrays from merely fast ones.

The Great Hypervisor Bake-off: VMware ESX vs Oracle VM

This is a very simple post to show the results of some recent testing that Tom and I ran using Oracle SLOB on Violin to determine the impact of using virtualization. But before we get to that, I am duty bound to write a paragraph of text featuring lots of long sentences peppered with industry buzz … Continue reading The Great Hypervisor Bake-off: VMware ESX vs Oracle VM →

ASM Rebalance Too Slow? 3 Tips To Improve Rebalance Times

I've run into a few customers recently who have had problems with their ASM rebalance operations running too slowly. Surprisingly, there were some simple concepts being overlooked - and once these were understood, the rebalance times were dramatically improved. For that reason, I'm documenting the solutions here... I hope that somebody, somewhere benefits... 1. Don't … Continue reading ASM Rebalance Too Slow? 3 Tips To Improve Rebalance Times →