Category: Storage

Storage is the foundation on which database performance is built. Latency, throughput, and consistency at this layer directly shape how systems behave under load.

While often abstracted away in modern architectures, storage characteristics continue to define the limits of what databases can achieve – especially as workloads become more demanding and less predictable.

New installation cookbook for SUSE Linux Enterprise Server 11 SP3

Exactly what it says on the tin, I've added a new installation cookbook for SUSE 11 SP3 which creates Violin on a set of 4k devices. I've started setting the add_random tunable of the noop I/O scheduler because it seems to give a boost in performance during benchmarking runs. If I can find the time, I … Continue reading New installation cookbook for SUSE Linux Enterprise Server 11 SP3 →

Postcards from Storageland: Two Years Flash By

The start of March means I have been working at Violin Memory for exactly two years. This also corresponds to exactly two years of the flashdba blog, so I thought I'd take stock and look at what's happened since I embarked on my journey into the world of storage. Quite a lot, as it happens... … Continue reading Postcards from Storageland: Two Years Flash By →

More Problems with Oracle’s Support of 4k Devices

This is going to be another one of those posts, a bit like this one, that discuss the use of Oracle's database product with Advanced Format devices. I wish there weren't so many of these posts, but it seems that Oracle has a lot of issues with it's implementation of 4k support. (Before reading on, … Continue reading More Problems with Oracle’s Support of 4k Devices →

Oracle ASMLib: Physical and Logical Blocksize

This article is about the use of Advanced Format devices on Oracle's ASMLib kernel library for Linux. For background, read this page on 4k sector sizes first, otherwise it might all sound like nonsense. Mind you, it mind sound like nonsense anyway, I can't guarantee anything here. By the way, a big hello to my … Continue reading Oracle ASMLib: Physical and Logical Blocksize →

Oracle AWR Reports: Understanding I/O Statistics

One consequence of my job is that I spend a lot of time looking at Oracle Automatic Workload Repository reports, specifically at information about I/O. I really do mean a lot of time (honestly, I'm not kidding, I have had dreams about AWR reports). One thing that comes up very frequently is the confusion relating … Continue reading Oracle AWR Reports: Understanding I/O Statistics →

New script for setting up multipath.conf entries

I've added a new script to the Useful Scripts page called setup-violin-mpath.sh which automates the process of creating entries for the /etc/multipath.conf file on Red Hat 6 / Oracle Linux 6. As the name suggests, I wrote it with Violin devices in mind, but there should be overlap with other storage which will potentially make … Continue reading New script for setting up multipath.conf entries →

Oracle Fixes The 4k SPFILE Problem…But It’s Still Broken

As anyone familiar with the use of Oracle on Advanced Format storage devices will know to their cost, Oracle has had some difficulties implementing support of 4k devices. Officially, support for devices with a 4096 byte sector size was introduced in Oracle 11g Release 2 (see section 4.8.1.4 of the New Features Guide) but actually, if the … Continue reading Oracle Fixes The 4k SPFILE Problem…But It’s Still Broken →

Oracle Exadata X4 (Part 2): The All Flash Database Machine?

This article looks at the new Oracle Exadata X4-2 Database Machine from Big Red. In part one I looked at the changes made from the X3 model (more stuff) as well as the implications (more license bills). I also covered some of the confusing and bewildering descriptions Oracle has used to describe the flash capacity … Continue reading Oracle Exadata X4 (Part 2): The All Flash Database Machine? →

Predictions for 2014: DataBase-as-a-Service

It's that time of year again where lots of people write articles which begin with the words "It's that time of year again..." and make endless references to crystal balls, tea leaves and the benefits of hindsight. But not me, I'm not descending into cliché. Apart from that first sentence, which with the benefit of … Continue reading Predictions for 2014: DataBase-as-a-Service →