Clickstream

Unintended Meaning in Your URL?

At least I didn't make this mistake when I chose Third Nature as a company name. I think my favorite is Go Tahoe.

Posted by Mark Saturday, August 26, 2006 11:40:00 AM | permalink | (0) comments

Backups are a Good Thing

Company taken out by bad database backups. My guess is that they didn't test the other half, wherein things are restored from backup. Reminds me of the joke song that was circulating a few years ago:

Yesterday,
All those backups seemed a waste of pay.
Now my source files have all gone away.
Oh I believe in yesterday.

Suddenly,
There's not half the files there used to be,
And there's a milestone hanging over me.
The system crashed so suddenly.

I pushed something wrong
What it was I could not say.
Now all my data's gone
and I long for yesterday-ay-ay-ay.

Yesterday,
The need for back-ups seemed so far away.
I knew my data was all here to stay,
Now I believe in yesterday.

Posted by Mark Wednesday, August 16, 2006 10:08:00 PM | permalink | (0) comments

Sun and Greenplum's Overstated Appliance Throughput Numbers

I was digging into the technical details of Sun's "Thumper" data appliance (a dual-CPU dual core rack unit that can hold a massive 24 TB of data) and ran into the overblown claims problem that seems rampant in all vendors selling into the high end of the market.

In this case it's overstated system I/O throughput. Here's the clip straight from Greenplum's site on the Bizgres MPP/Sun deal:

• Scan 1 Terabyte of data in 60 seconds.
• Leverages the first and only data server that combines a 4-way server with 24TB of storage in a single integrated system.

If you take their claims at face value, scanning 1 TB of data in 60 seconds at low cost is an impressive achievement. The problem is that to get there requires a serious hardware investment and not just one 4-core unit . The facts are pretty simple:

The documented I/O rate is 2 GB/sec from disk to memory for one 4 core unit (third item under "at a glance")
1 TB of data at 2 GB/sec means one unit can process 1 TB in 500 seconds, or 8 minutes 20 seconds. That's a lot more than 1 minute.
We need a little over 8 units (16 GB/sec) to achieve a TB/minute scan rate.
If we use the $32,995 price (from Sun's online store) for a 12 TB unit rather than the 24 TB unit mentioned above, the cost will be $263,960. The 24 TB unit mentioned above would set us back $559,960.

That's a lot of juice to get a 1 TB scan rate. The problem with this marketing message is that they are trying to mix a performance claim at the high end with a capacity claim at the low end. I could get the 1 TB scan rate with a rack of white-box opteron PCs and Bizgres MPP and come in a lot lower than $263,960. All I would give up is about 100 TB of additional capacity.

This is why you should always read the specs before taking performance claims at face value.

Posted by Mark Monday, August 14, 2006 9:58:00 AM | permalink | (0) comments

Seth Godin on BI (sort of)

Question: Why don’t you check your Technorati ranking?

Answer: Because the data won't change my actions. Getting data for no good reason just drives you crazy. The secret is to get very flexible in the face of data you care about - changing your x every time you see y changes - and incredibly inflexible in the face of data you don't care about.

This is the heart of why a lot of people have problems with BI. It's from ten questions Guy Kawasaki asked Seth Godin.

Posted by Mark Tuesday, August 08, 2006 9:44:00 PM | permalink | (0) comments

Java: Land of Nouns

There are some visualization libraries I want to use and that means I need to learn more Java than I know, so I'm working my way through "Head First Java" with periodic breaks to swear at verbosity and the ironic lack of verbs. I stumbled on this post and I think he's described why I like C/Python/YouNameIt better than working with Java (except that I don't like Smalltalk or LISP either).It's kind of long-winded at the beginning, so I suggest skimming down to the halfway point before the substance of functional ordination hits.

Read Execution in the Kingdom of Nouns

Posted by Mark Friday, August 04, 2006 1:48:00 PM | permalink | (0) comments

Deploying BIRT

Jason Weathersby has a good article describing how to deploy BIRT, something that can be confusing at times due to the number of deployment options. Link

Posted by Mark Thursday, August 03, 2006 10:54:00 AM | permalink | (0) comments