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.
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.
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
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.
When I was a child, about four or five years old, my dad told me a joke. It wasn't a very funny joke, but it stuck in my mind because of what happened next. The joke went like this: Dad: "What's big at the bottom, small at the top and has ears?" Me: "I … Continue reading Understanding Disk: Caching and Tiering
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. Nate believes that all English people live in the Dickensian London of the 19th century and speak in Cockney rhyming slang. I hate to disappoint, … Continue reading Oracle SLOB On Solaris
This article is aimed at anyone considering making the move into technical presales who currently works in a professional services, consultancy or support role, or as customers and end-users. You will notice that the title of the article has a question mark at the end - that's because I don't have the answer - and I … Continue reading How To Succeed In Presales?
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
Like most people, I have a panel on the right hand side of my blog which contains my blogroll, i.e. a list of links to the blogs of other people I respect and admire. And like most people in the Oracle world, up until today it was full of the same names you always see. … Continue reading A New Approach To My Blogroll
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
flashdba 