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 … Continue reading Paris Oracle Meetup (Jeudi 26 Mars 2015 @ 7pm)
Author: flashdba
Postcards from Storageland: Three Years At Violin
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 … Continue reading Postcards from Storageland: Three Years At Violin
Understanding Flash: Fabrication, Shrinkage and the Next Big Thing
NAND flash manufacturers have been shrinking transistors for decades, but 2D planar NAND is hitting its physical limits. This article explains process geometries, 3D NAND as the answer, and why new memory technologies face a billion-dollar barrier to market.
Oracle Exadata X5: The Road To Ten Billion Dollars
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 … Continue reading Oracle Exadata X5: The Road To Ten Billion Dollars
Deprecation of Non-CDB Architecture in Oracle 12c
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). … Continue reading Deprecation of Non-CDB Architecture in Oracle 12c
Understanding Flash: Floating Gates and Wear
NAND flash wears out because repeated program and erase operations degrade the oxide layer in floating gate transistors. This article explains how flash cells store data and why wear affects SLC, MLC and TLC differently.
Oracle AWR Reports: When IOStats Lie
If you've been unfortunate enough to follow my dithering on Twitter recently you'll know that I've been lurching between thinking that there is and isn't a problem with Oracle's tracking of I/O statistics in its AWR reports. I'm now convinced there is a problem, but I can't work out what causes it... so step 1 … Continue reading Oracle AWR Reports: When IOStats Lie
New Cookbook: Oracle Linux 6 Update 5 within an Oracle VM Template
I've posted a new installation cookbook for using Oracle within a virtual machine running on Oracle VM. Surprisingly, I was unable to come up with a satisfactory method of accessing external storage that did not involve the use of Oracle ASMLib... Oracle Linux 6 Update 5 within an Oracle VM Template
Understanding Flash: Unpredictable Write Performance
Not all NAND flash writes are equal. MLC flash has fast pages and slow pages, creating unpredictable write latency unless the storage controller manages them intelligently. This article explains why write performance varies and what enterprise arrays do about it.
Oracle AWR Reports: When Averages Lie
I was recently contacted by a customer who runs a busy ERP system on their Oracle database. Their users have been screaming for some time about unpredictable performance, where application screens which would usually open in under a second suddenly take an age. ERP systems are legendary for this, of course, because as each screen … Continue reading Oracle AWR Reports: When Averages Lie
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