Guest Post This is another guest post from my buddy Nate Fuzi, who performs the same role as me for Violin but is based in the US instead of EMEA. Because he's an American, Nate believes that "football" is played using your hands and that the ball is actually egg-shaped. This is of course ridiculous, … Continue reading Oracle, Parallelism and Direct Path Reads… on Flash
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.
Oracle 12.1.0.2 ASM Filter Driver: Advanced Format Fail
[Please note that a more up-to-date post on this subject can be found here] In my previous post on the subject of the new ASM Filter Driver (AFD) feature introduced in Oracle's 12.1.0.2 patchset, I installed the AFD to see how it fulfilled its promise that it "filters out all non-Oracle I/Os which could cause accidental overwrites". … Continue reading Oracle 12.1.0.2 ASM Filter Driver: Advanced Format Fail
Oracle 12.1.0.2 ASM Filter Driver: First Impressions
This is a very quick post, because I'm about to log off and take an extended summer holiday (or vacation as my crazy American friends call it... but then they call football "soccer" too). Before I go, I wanted to document my initial findings with the new ASM Filter Driver feature introduced in this week's … Continue reading Oracle 12.1.0.2 ASM Filter Driver: First Impressions
New section: Oracle SLOB Testing
For some time now I have preferred Oracle SLOB as my tool for generating I/O workloads using Oracle databases. I've previously blogged some information on how to use SLOB for PIO testing, as well as shared some scripts for running tests and extracting results. I've now added a whole new landing page for SLOB and … Continue reading New section: Oracle SLOB Testing
Understanding Flash: SLC, MLC and TLC
SLC, MLC and TLC NAND flash differ in how many bits each cell stores. More bits per cell means lower cost and higher density – but slower performance and reduced endurance. This article explains the trade-offs for enterprise storage.
Understanding Flash: Blocks, Pages and Program / Erases
NAND flash memory stores data in pages but erases in blocks – a fundamental asymmetry that shapes everything from SSD performance to all-flash array design. This article explains the program/erase cycle and why it matters for database storage.
New My Oracle Support note on Advanced Format (4k) storage
In the past I have been a little critical of Oracle's support notes and documentation regarding the use of Advanced Format 4k storage devices. I must now take that back, as my new friends in Oracle ASM Development and Product Management very kindly offered to let me write a new support note, which they have … Continue reading New My Oracle Support note on Advanced Format (4k) storage
Understanding Flash: What Is NAND Flash?
NAND flash memory was invented in 1981 by Dr Fujio Masuoka at Toshiba. This article explains how flash works, why it differs from EPROM and EEPROM, and why program and erase operations behave differently.
Understanding Disk: Caching and Tiering
Caching and tiering promise to hide the performance cost of spinning disk – but both rely on predicting the unpredictable, and the slowest tier always waits.
The Ultimate Guide To Oracle with Advanced Format 4k
It's a brave thing, calling something the "Ultimate Guide To ..." as it can leave you open to criticism that it's anything but. However, this topic - of how Oracle runs on Advanced Format storage systems and which choices have which consequences - is one I've been learning for two years now, so this really … Continue reading The Ultimate Guide To Oracle with Advanced Format 4k
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