![]() ![]() This mainframe was used to do the computing for most of the scientific work on campus, and scientific computing was almost entirely done in Fortran. Later on, I ran across references to similar tests at other schools, with similar results. Roughly 90% of the people they asked this said that they'd want the faster code. They asked lots of users of the Fortran code whether they would prefer their programs to catch all arithmetic errors if this meant that the code ran slower, or if they would prefer faster code that sometimes didn't catch errors. The local gang didn't believe this, so they did a bit of a survey. The vendor said they did this because they had found that most customers preferred faster code. The compiler had an option to generate such tests, but it was off by default. The hardware gave interrupts for floating-point overflows, but for integers, it just set a flag bit, and you needed to test that flag to catch overflows. They found that fully half the runs produced at least some incorrect output due to undetected integer overflows. ![]() I remember back in the 1970s, when I was at a large university that shall remain unnamed, and a bunch of CS people did a detailed study of the Fortran that accounted for fully half the runs on the campus's central mainframe (which shall also remain unnamed). There is evidence that people aren't generally that intelligent. Well, I'd be a bit careful about making such general statements. ![]() There isn't anything wrong with preferring fast incorrect results over slow correct results, but most people probably want slow and correct to be the default if given the choice. Unfortunately for Both us and RH, we don't like to update either, and even when RH has proven an update solves the problem, it's hard to get the Admins to actually update the boxen. (Course that is more a dig on HP, Veritas, EMC and some other "Enterprise Software" companies.) In fact I have a hard time sometimes of getting our Admins to open tickes with the *right* vendor, because they'd rather open a ticket with RH, because it gets solved sooner. Sometimes it ends with: "This was fixed in 4.5 please update." Sometimes it ends with "This is a bug, and here is the HF, please update to the released version when it becomes available." We're still running AS4U4 in some places and RH has worked with us to track down bugs. We've had to run a modified GCC for a while and Red Hat, *again* didn't say "You've changed it, so support for you." What they *did* say was, "Can you reproduce this on *our* gcc?" Which again is better than We've gotten from some other vendors. Red Hat does *not* tell us: "Oh, I'm sorry you're not running the latest support pack, no support for you." I'm working at a very large Wall Street firm. I want Linux to succeed and prefer it over the popular alternative. ![]() Until the players selling support realize all of this, Linux will be a difficult sell for such key systems (and the PHBs all think ALL their systems are mission-critical). We have to wait and be sure the patch is stable and provides an improvement without risking our mission. We don't update needlessly, and we certainly don't update to 'today's' patch. More, they won't support a system that doesn't have the latest updates, which is a problem on mission-critical systems. As indicated here, change something to fix a bug, and you don't get support for that piece anymore. But they don't perform enterprise support. want to be enterprise systems, and claim to offer enterprise support. I have a friend who runs mega-million-dollar, mission-critical systems and they've had to move off of Linux in favor of (Sun? Don't remember right now). And this has been an ongoing issue with Linux adoption. ![]()
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