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 the hybrid approach, so now it’s time to cover the other two.

SSD or CFM: The (more...)

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 on anybody’s mind is usually: how big is it?

Yet surprisingly, at least when it comes to All Flash Arrays, (more...)

Goodbye Violin… Available For Hire!


There’s a joke among some of the longer-serving employees of Violin Memory that “Violin years” are like dog years: every normal year feels like a decade. It’s not meant in a negative way, it’s just that things change so quickly and dramatically in the flash industry that whenever we take a moment to look back it seems impossible to believe that it was only a few years ago when flash was considered a new technology and we were (more...)

OUG_SCOT: I was on fire and then the fire alarm went off

it’s been a couple of months since my session at the oug_scot and I feel it’s enough time to write about it…

First of all – it was awesome!

I have never been to a user conference other than the ilOUG in Israel. I went to the Oracle Open World couple of years ago (and I’m not going this year :-( ) but it was nothing alike…

The user group was at a lovely place near (more...)

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 in my existing disk array?

Data Centre Dinosaurs

Disk arrays – and in this case we are mainly talking about (more...)

Oracle’s ASM Filter Driver Revisited


Almost exactly a year ago I published a post covering my first impressions of the ASM Filter Driver (ASMFD) released in Oracle, followed swiftly by a second post showing that it didn’t work with 4k native devices.

When I wrote that first post I was about to start my summer holidays, so I’m afraid to admit that I was a little sloppy and made some false assumptions toward the end – assumptions (more...)

All Flash Arrays: What Is An AFA?

All Flash Arrays - Hybrid, SSD-based or Ground-Up

For the last couple of years I’ve been writing a series of blog posts introducing the concepts of flash-memory and solid state storage to those who aren’t part of the storage industry. I’ve covered storage fundamentals, some of what I consider to be the enduring myths of storage, a section of unashamed disk-bashing and then a lengthy set of articles about NAND flash itself.

Now it’s time to talk about all flash arrays. (more...)

Was I Mentioned During Oracle’s Q4 2015 Results Call?


In a proud moment for me, it appears that Mark Hurd, CEO of Oracle, has mentioned my flashdba blog during the Oracle Q4 2015 results call. At least, that’s what I’m reading into this section from the transcript published by Seeking Alpha:

We grew in storage in the quarter and this is — really we are going through a shift in storage now. We released our SAN product FS1 in the quarter which (more...)

Oded’s Session on Security in the Cloud is now (oug_scot)

Oded Raz, my colleague and friend is on right now, talking about security in the cloud in the Scotland OUG conference.
Since the room is full, I had to leave to make some more space to the participants…

Oded at Scotland OUG

In the mean time, I was taking a walk around this nice complex and found the visitor demo room for hardware and engineered systems. I took some pictures:

ZFS storage and Solaris Servers

Exadata racks on display

My first session will start in a couple of (more...)

Live Blogging: Oracle User Group Conventions Israel and Scotland

Just a quick note – I was quite busy in the last few days – first there was the Israeli ilOUG convention (it’s still on) but I had to leave early since today I’m speaking at Scotland!

So today I’m speaking at 15:25 – my session is about “Adding Real Time Reporting to Your Database: Oracle In Memory Option”. This is a great session I gave last year in ilOUG SIG group and I added (more...)

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


So this is it – the last article in my mini-series on understanding flash. This is the bit where I draw it all together in a neat conclusion that makes you think, “Yes! That was worth reading”. No pressure eh?

So let me start with the conclusion first: as a storage medium, NAND flash is a royal pain in the ass.


Why? Well, let’s look back at what we’ve learned in the previous 9 (more...)

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 words. Forgive me, it’s just the way I’m wired.

It is increasingly common these days to find database environments running (more...)

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 Overbalance

Every time you run an ALTER DISKGROUP <NAME> REBALANCE operation you initiate a large amount of I/O workload as (more...)

OAUG BI Publisher SIG

First off, if you are not familiar with the term SIG, it stands for Special Interest Group.  OAUG facilitates a number of SIGs to bring users together that share common or industries concerning certain Oracle products.

Unfortunately, the BI Publisher SIG has been offline for a number of years and has not been given the attention it needs to be a useful resource for members of OAUG.  Well… I’m getting the band back together and (more...)

Annual Report from WordPress

Recently, I received my annual report from WordPress/Jetpack.  I have always enjoyed these reports, so I thought I would make it public.

For the complete report, view it here: PSST0101 – 2014 Year in Blogging

Here’s a couple of excerpts:

Crunchy numbers

Madison Square Garden can seat 20,000 people for a concert. This blog was viewed about 67,000 times in 2014. If it were a concert at Madison Square Garden, it would take about 3 (more...)

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My lucky find for ORA-01720: Grant Option Does Not Exist.

Strangest thing happened the other day during a customer upgrade.  Our automated scripts were in the process of creating a view and I received the error:

ORA-01720: Grant Option Does Not Exist.

OK…..  I get it…  BUT…. I didn’t even execute a GRANT statement!?  I was just executing a CREATE OR REPLACE VIEW…. what gives?

Doing some searching online, I didn’t find too much that fit my issue.  Everyone was getting (more...)

Printing Attachments in Oracle 12.2: How does it Stack Up?

With the release of EBS 12.2, Oracle is making the claim that they have improved the attachment printing process. After reviewing the integration, I completely disagree; they have not given users a better solution.  No matter how you slice it, Oracle EBS customers are no further ahead with (more...)

Forms Personalization: Calculating an Item Value

I received the following comment recently on an older Forms Personalization post:

how can i get result from the following equation through personalization

i want to know what is the syntax and what is the required steps to get the result automatically