Postcard from Oracle OpenWorld 2014: The Oracle FS1 Flash Array

OOW14

A couple of weeks ago I wrote a post about my trip to Oracle OpenWorld 2014 and the surprise announcement of the Oracle FS1 Flash Array. I posted it on the Violin Memory corporate website here:

http://www.violin-memory.com/blog/postcard-oracle-openworld-2014-the-oracle-fs1-flash-array/

Follow the link to find out whether I thought it was the most amazing product in the history of storage, or simply a rehashed Pillar Axiom hybrid array with some SSDs and a ton of marketing.


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Understanding Flash: Garbage Collection Matters

garbage-collection

In the last post in this series I discussed some of the various tasks that need to be performed by the flash translation layer – the layer of abstraction that sits between us and the raw NAND flash on which we desire to store our data. One of those tasks is the infamous garbage collection process (or “GC”) – and in these next couple of posts I’m going to look into GC a little deeper.

But (more...)

Understanding Flash: The Flash Translation Layer

electronics

A couple of posts ago in this series, I explained how a NAND flash die is comprised of planes, which contain blocks, which contain pages… which contain individual cells of data. Read operations take place at the page level, as do write operations (although we call them program operations in the flash world). But crucially, erase operations take place at the block level and so affect multiple pages.

Erases are also (more...)

Oracle, Parallelism and Direct Path Reads… on Flash

3000-open-case

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, because as the entire rest of the world knows, this is football whereas the game Nate is thinking of is (more...)

Viewing ASM trace files in VIM: Which Way Do You Use?

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A couple of people have asked me recently about a classic problem that most DBAs know: how to view ASM trace files in the VIM editor when the filenames start with a + character. To my surprise, there are actually quite a few different ways of doing it. Since it’s come up, I thought I’d list a few of them here… If you have another one to add, feel free to comment. I know that (more...)

Oracle 12.1.0.2 ASM Filter Driver: Advanced Format Fail

wrong-way

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“. However, because I was ten minutes away from my summer vacation at the point of finishing that post, I didn’t actually get round to writing about what (more...)

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 12.1.o.2 patchset.

Currently a Linux-only feature, the ASM Filter Driver (or AFD) is a replacement for ASMLib (more...)

New AWR Report Format: Oracle 11.2.0.4 and 12c

statistics-and-graphs

This is a post about Oracle Automatic Workload Repository (AWR) Reports. If you are an Oracle professional you doubtless know what these are – and if you have to perform any sort of performance tuning as part of your day job it’s likely you spend a lot of time immersed in them. Goodness knows I do – a few weeks ago I had to analyse 2,304 of them in one (long) day. But for anyone (more...)

New section: Oracle SLOB Testing

slob ghost

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 a complete guide to running sustained throughput testing.

Why would you want to run sustained throughput tests? Well, one (more...)

Understanding Flash: SLC, MLC and TLC

slc-mlc-tlc-fruitmachine

The last post in this series discussed the layout of NAND flash memory chips and the way in which cells can be read and written (programmed) at the page level but have to be erased at the (larger) block level. I finished by mentioning that erase operations take substantially longer than read or program operations… but just how big is the difference?

Knowing the answer to this involves first understanding the different types of flash (more...)