Computer World. Матросова Т.А. - 94 стр.

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reliability has never been a high priority – either for the industry or for users. Like a
patient seeking treatment from a therapist, PCs must want to change.
«When a 2000-user mainframe crashes, you don't just reboot it and go on
working», says Stephen Rochford, an experienced consultant in Colorado Springs,
Colorado, who develops custom financial applications. «The customer demands to
know why the system went down and wants the problem fixed. Most customers with
PCs don't have that much clout».
Fortunately, there are signs that everyone is paying slightly more attention to the
problem. Users are getting fed up with time-consuming crashes – not to mention the
complicated fixes that consume even more time – but that's only one factor. For the
PC industry, the prime motives seem to be self-defense and future aspirations.
With regard to self-defense: Vendors are struggling to control technical-support
costs, while alternatives such as network computers (NCs) are making IT
professionals more aware of the hidden expenses of PCs. With regard to future
aspirations : The PC industry covets the prestige and lush profit margins of high-end
servers and mainframes. When the chips are down, high availability must be more
than just a promise.
That's why the PC industry is working on solutions that should make crashes a
little less frequent. We're starting to see OSes that upgrade themselves, applications
that repair themselves, sensors that detect impending hardware failures, development
tools that help programmers write cleaner code, and renewed interest in the time-
tested technologies found in mainframes and mission-critical embedded systems. As
a bonus, some of those improvements will make PCs easier to manage, too.
But don't celebrate yet – it's hardly a revolution. Change is coming slowly, and
PCs will remain the least reliable computers for years to come.
Why PCs Crash
Before examining the technical reasons why PCs crash, it's useful to analyze the
psychology of PCs – by far the biggest reason for their misbehavior. The fact is, PCs
were born to be bad.
«The fundamental concept of the personal computer was to make trade-offs that
guaranteed PCs would crash more often,» declares Brian Croll, director of Solaris
product marketing at Sun Microsystems. «The first PCs cut corners in ways that
horrified computer scientists at the time, but the idea was to make a computer that
was more affordable and more compact. Engineering is all about making trade-offs.»
It's not that PC pioneers weren't interested in reliability. It's just that they were
more interested in chopping computers down to size so that everybody could own
one. They scrounged the cheapest possible parts to build the hardware, and they took
dangerous shortcuts when writing the software.
For instance, to wring the most performance out of slow CPUs and a few
kilobytes of RAM, early PCs ran the application program, the OS, and the device
drivers in a common address space in main memory. A nasty bug in any of those
components would usually bring down the whole system. But OS developers didn't
have much choice, because early CPUs had no concept of protected memory or a

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