Monthly Archives: April 2013

Gigabyte versus Gibibyte

Are the hard drive vendors screwing us?

the answer is no. At least when it comes to the number of bytes they promise you can store on their drives they’re not. Oh really?

In July 2012 I wrote a blog post on “saying what you mean to say“, so people cannot misinterpret what you’re trying to point out. Gigabyte, Gibibyte, Joules, Calorie, kilo Calorie, degrees Celsius, but not degrees kelvin (it’s just kelvin or capital K).

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Spring 2013 is finally taking off!

Winter is coming going

And now for a little non-technical post from me: over here, in Europe, we’ve been suffering from a long period of time we call “winter”, although having 5C / 41F in March and April is way below average. Last week we enjoyed a day of above 15C / 59F and this week it seems temperatures are finally staying at reasonable levels. We’re able to go outside without a coat and even stay there a while without getting cold!

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Fibre Channel Routing: EMC Ask the Expert on ECN

Fibre Channel Routing

From Monday April the 15th to May 1st 2013 EMC is hosting yet another “Ask the Expert” discussion on ECN. This time it’s about Fibre Channel Routing.

What is it, what’s it used for and how do you know if you want it?

Take a look at the discussion and join me and my friends Allen Ward and Mr Dynamox on ECN!

And although we close the topic on May 1st, we’ll wrap up LIVE from EMC World in Las Vegas in the EMC Elect corner! So if you’re there from May 6 to May 9, make sure to look out for us. As far as I know the Elect corner will be next to the Blogger’s area, close to the Pavillion.

EMC World 2013, the final countdown has started!

The countdown has started

Just 3 weeks and a few days to go and it’s EMC World again! Time to meet my old and new friends and finally getting some rays. the one thing I’ve been missing the last few weeks it’s the sun and I guess most Europeans agree with me. Don’t know what it’s like in other parts of the world, but I certainly need more heat than what we’re having now.

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SCSI, (P)ATA, SAS, NL-SAS and SATA, what’s the difference? (part 2)

So what else is there that differentiates SCSI, (P)ATA, SAS, NL-SAS and SATA?

Size matters

In part 1 we talked about Rotations Per Minute and Command Queuing, but what else is there that makes a certain drive a better choice than any other? Other differences are the size of the platters. Commonly used are 3.5 inch and 2.5 inch. Although it makes sense that smaller platters can rotate faster than larger platters in the end only the size of the drive cage matters. It’s in fact somewhat weird that most 2.5 inch drives now rotate at 10k RPM and the 3.5 inch drives at 15k. Being able to cool the device is probably the main reason why a 10k drive only spins at 10k RPM. If it would rotate any faster, it would heat up more and heat dissipation could become a serious problem. So if you need a high GB per square meter density and performance doesn’t really matter, then the 2.5 inch drives make sense, but if performance is the key differentiator, the more IOps you can squeeze out of each drive, the better. And since we’re not discussing data center designs here, only quality / performance counts.

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