Paper money magnetic?

So I read somewhere (perhaps MAKE) that the ink used to print paper money in the US contains iron and is therefore magnetic. Zach and I decided we had to try this at lunch and had this fun with a $2 bill and a stack of strong neodymium magnets:

It wasn’t strong enough to lift the bill but you can definitely see the magnet’s effect. It seems like only the ink around the outer part of the bill worked and this was with one of the newer US bills.

Try it yourself! It’s a great Friday afternoon distraction.

magnet, money, currency, magnetic, fun

This Week in Tech Podcast – Feed your Inner Geek!

TWiTThere are a lot of dry monotone technology podcasts out there, but Leo Laporte’s TWiT podcast isn’t one of them. Every week Laporte brings together a cast of industry leaders to discuss exciting technology topics ranging from the latest offerings from Microsoft to what’s new on RFID hacking.

Laporte, along with regulars Patrick Norton and John C. Dvorak are joined by other technology professionals for this roundtable discussion. Together they run through a dozen or so top technology each week. Typically these podcasts are a bit over an hour, but if you have a long drive like I do, it’s an hour well spent.

If you work in or are studying technology, especially information technology, you should check out the TWIT podcast. Get the MP3 or AAC version on iTunes!

technology, tech, podcast, mp3

10 Writing Tips

Alexander over at PositiveSharing.com has posted his Top 10 tips for productive, creative, fun writing.

So how’d [write a whole book in twenty days]? Well the answer is obvious isn’t it? Clear goals, hard work, perseverance, sticking to it, eliminating distractions and writing no matter what, right?

Wrong.

Wrong, wrong, wrong. I tried that. Didn’t work. So I tried the exact opposite and that worked.

Like most of Alexander’s posts, this list is both highly applicable and refreshingly unconventional. Some of these things I find I’ve already been doing and others I’ll have to remember to try.

While my publisher would probably take issue with #9 (No deadlines or goals) I’m sure these tips will find their way into how I blog and work on my books.

writing, blogging

Best bumper sticker ever

Living in a condo association you get used to folks coming and going, you just cross your fingers and hope that with this spin of the wheel you won’t get some nutty redneck. Well, before I’d even met my new neighbors I saw this bumper sticker on their car.

My Boss Is An Italian Plumber


Needless to say I stopped worrying immediately.

These are available through ThinkGeek, of course…

geek, bumper sticker, mario, mario brothers, nintendo, my boss is an italian plumber

RAID 5 and Oracle Databases

While researching the effect of RAID 5 disk configuration on Oracle databases I came accrost more than I thought I expected on the topic.

With disk as cheap as it is today there is no reason to ever use RAID 5 on an Oracle database. Even for a database which sees only a moderate amount of updates the performance loss incurred by using RAID 5 is too high. RAID 1 or some combination of RAID 1 and RAID 0 should be used when high availability is required. Database 10g users should also consider allowing Oracle’s new Automatic Storage Management to handle redundancy on un-mirrored disks (or even raw partitions.)

But don’t take my word for it. Here are some opinions from some notable Oracle administrators:

Oracle Database RAID 5
Mark Rittman

No RAID5. Use RAW whenever possible and consider RAID10 or 0+1. RAID 5 can severely affect performance on highly updated databases.

Oracle Database Administration: The Essential Reference
David Kreines & Brian Laskey

RAID-5 is, in fact, very powerful and inexpensive. It is also a technology to be avoided in most cases when configuring your Oracle database! This may seem a harsh statement, but the reality is that although RAID-5 provides good levels of data protection at a low monetary cost, this comes at a very high cost for disk I/O. In particular, write operations on RAID-5 arrays can be orders of magnitude slower than the same operations on a single disk.

Oracle and RAID usage
Mike Ault

Use RAID10 when possible, RAID5 if it is not. Size the array based on IO needs first, then storage capacity and you can’t go wrong.

Disk Management for Oracle
Donald Burleson

Oracle recommends using (SAME) Stripe And Mirror Everywhere (a.k.a., RAID 1+0) for all systems that experience significant updates. This is because of the update penalty with RAID 5 architectures.

Using RAID 5 for a high-update Oracle system can be disastrous to performance, yet many disk vendors continue to push RAID 5 as a viable solution for highly updated systems.

RAID 5 is not recommended for high-update Oracle systems. The performance penalty from the parity checking will clobber Oracle performance.

If you’re still not convinced check out Baarf.com. This site is committed to the Battle Against Any Raid Five (or four or free, uh, three.) The site has links to several more articles exposing the perils of RAID 5.

oracle, rdbms, dba, systems administration, sysadmin, raid, raid 5