A Volatile Look At HSQLDB

Posted January 13, 2011 by designbygravity
Categories: Software

Tags: , , , ,

Recently, I had cause to look at HSQLDB, one of several pure Java databases out there. At my job, we use RDBMS technology to back our deductive database systems. As such, we have need for a small-scale development RDBMS to accompany larger enterprise-grade RDBMS’s. For several years we have used H2, and it has been good to us. It is small, fast, very complete and reliable.

However, a couple years ago H2 changes it’s on-disk storage system. The new storage system is neater and cleaner, but it had a side effect: H2 is now significant less concurrent. Our deductive engine is highly concurrent (we implemented a form of Actor concurrency before we knew what Actors were), and we routinely run hundreds of SQL queries simultaneously. We treat the RDBMS backend much like a NoSQL database, and really thrash it at times, especially before the caching and materialization layers kick in. In recent years, as every machine gained cores like mad, this has become a problem. H2’s lack of concurrent execution sometimes slows the system down to the point where even on small datasets, Postgres is faster, despite the network hop. (This is not a knock on H2; highly concurrent access is not a design goal that seems to be emphasized. Fair enough.)

So this is a problem, so I decided it was time to survey embedded DB’s again. In the past, I had looked at HSQLDB and Derby and rejected them for performance reasons. Perhaps, in the intervening three years something had changed?
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The Curious Case of Netflix Streaming Quality

Posted January 3, 2011 by designbygravity
Categories: Tech

We stream a lot of media in my house. Yes, we have a full Comcast triple-play package, and we take full advantage of on-demand programming. We have HBO and Showtime subscriptions. You’ll pry my TiVo from my cold, dead hands. No immediate danger of cutting the cable here.
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Is an Email Address a Social Contract?

Posted October 6, 2010 by designbygravity
Categories: Social Commentary, Tech

Tags: , ,

Seriously. If you know my email address, am I bound by some social custom to answer every email you send me? Within some particular time frame? Am I required to even read every email you send me?

A scenario:

  1. I have an email address.
  2. You send me an email
  3. I have, you know, a life. I don’t read your email for a couple days.
  4. You get annoyed at me for not answering, so you send another email: “Did you get my email?”
  5. I, still possessing a life, family and a job, still don’t read your email.
  6. You get downright pissed, and send me a screed as to my personal failings.
  7. Email checking finally bubbles to the top of my todo-list, and I read your first email. Possibly even respond to it.
  8. By the time I read your last email, I am baffled as to how my personal scheduling became offensive to you.

Been there? Me too.
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Must-Have Apps for My Droid-X

Posted September 30, 2010 by designbygravity
Categories: Software, Tech

Tags: , , ,

I’ve had the Droid-X since July; long enough to settle into a groove as far as applications go. These are my go-to apps; the ones I would recommend without hesitation.

Note that these apps are not all free; after spending $200 for a phone and $60/month for the phone, spending $5 for an app doesn’t bother me. My logic, doesn’t have to be yours. The links are not links into the Marketplace though most should lead you there eventually. No order or ranking implied, and the prices are merely what I found on the net.
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Can You Program a VCR? Are You Sure?

Posted September 30, 2010 by designbygravity
Categories: Social Commentary, Tech

Tags: , , ,

Anybody over say, thirty years old, will remember when VCRs ruled the TV recording roost. They were magical machines, allowing you to record your favorite shows at will, and then re-watch them while mostly skipping the commercials. Truly cool. Life changing. Amazing.

But do you remember what your parents (or perhaps your grandparents) reaction was? Do you remember how hard it was to teach them how to use the remotes? How you couldn’t easily explain that there was a separate tuner in the VCR, allowing them to record one channel while watching another? Some of you laughed at their confusion. Some of you no doubt cried in frustration.

In the end we are all tech support for someone, I suppose.

But do you recall the single defining visual of “old people” and their VCR’s?
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iPhone to Droid X: Lots More Good Than Bad

Posted August 10, 2010 by designbygravity
Categories: Tech

Tags: , , , , ,

It’s been almost 4 weeks now since I left my iPhone behind for a launch day Droid X. I gave my quick impressions earlier; now I want to dive a little deeper.

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iPhone to Droid X: Impressions of a Data Pig

Posted July 29, 2010 by designbygravity
Categories: Tech

Tags: , , , , ,

Two weeks ago I pulled the trigger. Two days prior I had stopped in my local Verizon store, said I wanted a Droid X. The next day, the rep called and said he had one for me, as long as I was in the store by 5pm the next day, launch day. After dropping my kids at camp, I hustled in at 10am sharp. By 10:40 I was out the door with my new beast. So what has it been like? Read the rest of this post »