Inside The Development of Windows NT: Testing

The Qube writes "As a followup to the in-depth story posted back in February regarding the history and the development of Windows NT, part 3 of the series of articles is now online. It discusses the software testing procedures inside Microsoft."

Comments

All jokes aside...

[KFury]

All jokes aside, the amount of testing and the build process for NT is one of the most tightly organized and comprehensive testing methodologies in existence.

Rather than take 'miller time' pot shots at Microsoft, the real takeaway is the understanding that, no matter how rigorous the testing and build process, there is a complexity limit where a unified one-organization nightly fix-build-test model simply can't provide a product of suitable quality.

Better to acknowledge the best-of-breed methodology Microsoft uses to test their OSes, and conclude that while this breed works okay for applications, a world-class operating system needs peer review and distributed open source development to create a quality, secure product.

Re:All jokes aside...

[asa]

"Better to acknowledge the best-of-breed methodology Microsoft uses to test their OSes...."

Except that this article says nothing about the testing methodology that Microsoft uses. It describes how Microsoft helps certain customers test deployment. Deployment testing has little or nothing to do with software testing.

This is an article about how Microsoft has the budget to help "special" customers with a free "service" (not software) and frankly, the bits about offering cash-strapped school systems free consulting and test deployments sounds a lot more like a Microsoft press release than a software testing case study.

I was genuinely hoping to read about their software QA process. What a waste of 5 minutes.

--Asa

Testing??? Not at all.

[the eric conspiracy]

No way this article is about software testing. This is about an evaluation lab where customers bring in their applications to show to Microsoft. It's a marketing puff-piece, that's all.

Where is the description of the test methodologies used? The bug escalation and change control systems? What sort of configuration control is used?

Seriously....

[wowbagger]

All the Q/A in the world does you no good if you don't act upon what Q/A has found.

I used to do driver development for NT4.0. As such, I had a "victim" machine and a "debugging" machine, linked via a serial cable. The victim runs my driver, and I do my development and debug using the debugging machine to access the kernel debugger on the victim.

A normal cycle of development went something like this:

1. { {{edit,compile} while errors} link } while errors
2. Download to victim
3. boot victim. Watch hundreds of assertion failures from the OS scroll by on debugging console.
4. Shut down debugger as it has leaked all available memory
5. Start debugger again
6. Load my driver and test.
7. locate bugs in my driver, begin again

Note: this was a fresh install of NT4.0 debugging, with SP4. No third party apps (other than my own) installed. This was using Microsoft's WinDBG.

Now, I don't know about Microsoft's developers, but I regard an assertion failure as a failure - i.e. a bug to be fixed. Having HUNDREDS of them in released code is just unacceptable. Using an ASSERT() as a debugging printf() is wrong.

So either a) the MS developers have a different view of things than I do, or b) the MS developers were allowing hundreds of easily identified problems to go into release.

Now, EVERY non-trivial software project's lead engineer must make a decision at every release - "Do I fix these bugs and slip the release, or fix these bugs in the next release?" And EVERY lead will allow some bugs to slip. Usually, those bugs are deemed minor - spelin mestaches (sic), layout errors, things like that.

But to have a) hundreds of assertion failures, which give you file and line number of the error, and b) a memory leak in your debugger bad enough that you can WATCH it leak away hundreds of megabytes of memory each time, and to allow that to go out? Ugh.

Now I am sure that MS Q/A found those errors - if not they are far more incompetent that I am willing to assume they are. So clearly Q/A was overruled by management - "We don't care, ship it anyway!"

And that is the central problem to ANY Q/A department - if management overrules them, and forces a shipment anyway, then how do you blame Q/A?

I've said this before, and I shall say it again now: this is one of the places a real ISO-9000 standard can be useful. If the spec sayth "Lo, and the release candidate code shall have no bugs open against it in the bug tracking system, and any bugs that exist shall be clearly targeted to later revisions, and Q/A shall findth no undocumented bugs in the code, or the release shall be slipped, and the bugs corrected, AMEN!" then Q/A can say "OK, if you want to throw our ISO-9000 cert out the door, then by all means override us and ship."

(Yes, that won't prevent management from simply targeting all bugs to a later revision and shipping, but it at least forces some consideration of the consequences to me made."

Quote from the Ky. Dept. of Ed. customer.

[hndrcks]

"We're hoping to get a long-term lifespan out of Windows Server 2003 without having to do major upgrading."

These guys obviously aren't students of "Licensing 6.0".

Re:Testing

[LaCosaNostradamus]

People that laugh at the products MS produces really do have to look hard at how THEY would manage and TEST 50 MILLION lines of code. With 50 million lines of code you're looking at virtually an infinate number of tests to run, which is obviously impossible to do. Thus you either have to roll out a product that hasn't been 100% tested because of its size or keep testing and never make money.

As part of the Microsoft culture, it appears that you've missed the point.

The problem is the 50 million lines of code itself.

I would have "managed" NT's testing by "not managing it" at all, and instead would have clipped out all those bells and whistles to make a much more trim and modular OS. The code base is unecessarily large, from a functional point of view.

But just like the current SUV problem in America, it appears that Microsoft is dancing a tango with the consumers. Microsoft produces shitty code that looks good on the screen, and the consumers say "ohh" and "ahh" while not minding the crashes and restrictions, and then Microsoft gets encouraged to produce more "pretty code". I don't consider this problem to be fixable ... we who know better and are less mediocre simply have to fend for ourselves and rely on the influence of our leadership to promote the Better Way. This is the slow method of providing a good example for others to follow, which is the only leadership that matters. Microsoft's billions are just a facade; consumer mediocrity is another facade; what will matter in the long run is bullet-proof code that more serves public needs instead of software-industry investors.