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Database Error Detection and Recovery

Posted by CowboyNeal on from the bringing-out-the-dead dept.

CowboyRobot writes "ACM Queue has an interview by Steve Bourne with Bruce Lindsay, responsible for a lot of the SQL and RDBMS we use today, in which they discuss error detection and recovery. My favorite part other than the photos is the definition of Heisenbugs - those problems that disappear only when you explicitly look for them."

15 of 163 comments (clear)

  1. this is to test a bug in slashcode by EnVisiCrypt · · Score: 3, Funny

    ignore this response.

    --


    *everything* is Orwellian to cats.
  2. Heisenbugs by base_chakra · · Score: 4, Funny

    "Heisenbug as originally defined--and I was there when it happened--are bugs in which clearly the behavior of the system is incorrect, and when you try to look to see why it's incorrect, the problem goes away.

    This is a really cool article, but it was especially fun to see the heisenbug mention. Years ago, some fellow CS people and myself conjectured a similar phenomenon that seemed to manifest once in a while, in which a computer malfunction goes away after one "proves" that there's no cause for the error to exist.

    Here's a list of heisenbug anecdotes, but note that some of these submissions aren't strictly heisenbugs.

    1. Re:Heisenbugs by JaredOfEuropa · · Score: 4, Funny

      I remember compaints about a Windows NT server slowing down to a crawl even when there weren't that many people using it. So the SysOp would fire up a few performance monitors and keep an eye on the thing. Sure enough: no slowdowns, no performance issues, normal operation. But every time when the guy would leave, the system would slow down again after 5 minutes or so. For a few days this had us stumped.

      Then someone figured out that the system had the 'pipes' screensaver on that came with NT3.51. Of course, as soon as we started to diagnose the machine, the screensaver would disappear. And yes... the screensaver turned out to be the culprit, sucking all the system resources away. We removed it and all was well.

      Does anyone know who coined the term 'heisenbug' by the way?

      --
      If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
  3. The Heart Monitor Case... by Anonymous Coward · · Score: 4, Funny

    BL: In the heart monitor case, you better keep the heart going, whereas in the Microsoft Word case, you can just give them a blue screen and everybody is used to that.

    SB: But also in the heart monitor case, it?s hard to ask users if they want to keep the heart going because the answer is pretty obvious, whereas in the Word case, you can ask the user in some cases what to do about it.

    New Microsoft Pace - Heart Monitor and Pacemaker

    STOP: 0x0000000A (0x0000015a, 0x0000001c, 0x00000000, 0x80116bf4)
    IRQL_NOT_LESS_OR_EQUAL - Beat.exe
    Please hold your breath while a dump file is created...

  4. Picture by bonzoesc · · Score: 4, Funny

    That picture is really something. I didn't know Gandalf wrote bsh.

  5. Good god, that picture! by Anonymous Coward · · Score: 4, Funny

    The guy looks like he's covered in coke dust.

    1. Re:Good god, that picture! by Anonymous Coward · · Score: 1, Funny

      He looks like they found him frozen in a cave.
      That was my first thought too! Unfrozen, caveman database genius.

  6. Heisenpages by Anonymous Coward · · Score: 2, Funny

    Web pages that disappear when you try to look at them....

  7. A man with one clock only thinks he knows the time by Anonymous Coward · · Score: 1, Funny

    A man with two clocks that agree has a much higher degree of certainty.

  8. Re:Make error message meaningful! by Anonymous Coward · · Score: 1, Funny

    This mean you have reboot Windows and the problem will magically solves itself.

  9. Cool! by Anonymous Coward · · Score: 2, Funny

    I just found my new avatar picture. :)

    ps: not a troll, this guy's a freakin genius. I hope I look like that in 20+ years.

  10. Re:A man with one clock only thinks he knows the t by Anonymous Coward · · Score: 1, Funny

    Of course, both clocks could be totally broken but have been set to the same (unchanging) time by obsessive/compulsive someone "tidying up". Then the clocks are each right twice a day but not when you think.

  11. Re:Heisen-whats? by fforw · · Score: 3, Funny
    Heisenbugs. Are there Heisen-features as well?
    yes. they exist but disappear once you try to use them. A direct result of featuritis.
    --
    while (!asleep()) sheep++
  12. Re:This is why MySQL ignites flamewars by Duncan3 · · Score: 1, Funny

    This article is about databases, why are you talking about MySQL... stay on topic please.

    --
    - Adam L. Beberg - The Cosm Project - http://www.mithral.com/
  13. Has language in CS matured? by sapgau · · Score: 2, Funny

    I couldn't help noticing Mr. Lindsay explanations of what a process would or could do. He kept describing it in the first person:

    - "You asked me to do X, I didn't do it."
    - "Aha, this seems like I should go further."
    - "Oh, I see this as one of those really bad ones."
    - "I'm going to initiate the massive dumping now."

    Obviously he is an expert in his field but I'm not sure if he talks this way because of his personality or because there isn't a vocabulary big enough to describe it.

    Would you imagine a medical doctor talking this way?

    - "So the white blood cells fight with the cancer cells: die evil cell, die!!"

    Or an engineer:

    - "The little peg ask it's big brother : can you help me convert this energy into circular motion?"