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...)
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...)
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...)
I’m delighted to say that this is another guest post from my good friend Nate Fuzi, who performs the same role as me for Violin but is based in the US instead of EMEA. Because he is American, Nate thinks that scones are called “biscuits”, that chips are called “fries” and that there is nothing – *nothing* – that cannot be improved with the simple addition of bacon. Clearly, something is fundamentally wrong with him (more...)
A quick post to say that this week, on Thursday 26th, I will be giving a talk (in English!) on the subject of Flash for DBAs (and architects, designers, developers, managers etc) at the Paris Oracle Meetup:
Flash for DBAs: A new technology is sweeping the world of storage. Flash, a type of non-volatile memory, is gradually replacing hard disk drives. It began in consumer electronic devices such as phones, cameras and tablets (more...)
A few weeks ago, in what seems to be a truly modern phenomenon, I became aware that it was my third anniversary of joining Violin after I noticed a number of people congratulating me on LinkedIn. In many ways it feels like I’ve already been here for a lifetime, but it was only twelve months ago I was trying to think of a suitable flash-based pun for the title of an article just like this one. (more...)
My good friend and colleague Liron Amitzi started his new Oracle Blog.
Here is a shout out to @amitzil and his new blog: good luck and have fun!
The thing I like the most about his new blog is the “Did you know” section.
In those posts he’s describing very short facts that people might not have known before, and could save some them a lot of time (or just be very educational).
I’m actually (more...)
Once, a very long time ago, I told an old joke about SQL and it was a huge success (not really).
This week I heard a joke that is slightly related to that joke and it made me giggle for a couple of minutes.
Those who know me, knows that I really like to hear jokes but I’m really terrible at telling them – but let’s go for it anyway.
2 DBAs NoSQL walk into (more...)
Semiconductor Fabrication Plant (picture courtesy of SemiWiki.com)
Before I draw this series on Understanding Flash to a close, I wanted to briefly touch on the subject of manufacturing. Don’t worry, I’ve taken heed of the kind feedback I had after my floating gate transistor blog post (“Please stop talking about electrons!“) and will instead focus on the commercial aspects, because ultimately they affect the price you will be paying for your flash-based (more...)
Now that the dust has settled on the announcement of Oracle’s new Exadata X5 Database Machine, I’ve been doing some research in order to update my History of Exadata post (it’ll be ready soon). While reviewing the datasheets and other collateral for the X5 I was struck by the meteoric increase in one particular statistic: the number of processor cores on each database server. Oracle is riding that Moore’s Law train all the way to the bank.
Back in July 2013, Oracle released the latest version of its flagship database product, Oracle 12c. Among the usual fanfare was information about a number of new options – including one known as Multitenant. With the Multitenant option, databases use a new architecture which features a container database (or CDB) which in turn contains one or more pluggable databases (or PDBs). Use of Multitenant requires a licence – which at the time of writing retails at $17,500 (more...)
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...)
One of the important characteristics of flash memory is wear. We know from previous articles in this series that flash packages consist of dies, which contain planes, which contain blocks, which in turn contain pages. We also know that these pages contain individual cells which store the bits of data… but to understand what wear is we need to look a little bit closer at those cells, where we will find something called (more...)
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:
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...)
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...)
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...)
I received the following comment recently on an older Forms Personalization post:
how can i get result from the following equation through personalization
K_LINES.LINE_VALUE = K_HEADER.K_VALUE/K_HEADER.PRIME_K_NUMBER
i want to know what is the syntax and what is the required steps to get the result automatically
Brought a couple new PCs up recently and ran into the subject nasty error when attempting to access EBS. We’ve run into this before and we usually get it worked out one way or another. This time proved to be a bit challenging for some reason… Thought I (more...)
So calling Google Reader dead may be a bit premature, but Googles announcement of their intention to kill their baby all but killed it. On monday it is RIP for the reader. I’ve gone through disbelief to mourning the loss to a search for a replacement that best emulates what (more...)