Categories
operating systems software business

Microsoft by the numbers

From correspondent AY:

150,000,000
Number of Windows 7 licenses sold, making Windows 7 by far the fastest growing operating system in history.
<10
Percentage of US netbooks running Windows in 2008.
96
Percentage of US netbooks running Windows in 2009.
9,000,000
Number of customer downloads of the Office 2010 beta prior to launch, the largest Microsoft beta program in history. [source]
24%
Linux Server market share in 2005.
33%
Predicted Linux Server market share for 2007 (made in 2005).
21.2%
Actual Linux Server market share, Q4 2009.

http://blogs.technet.com/b/microsoft_blog/archive/2010/06/25/microsoft-by-the-numbers.aspx

Those last numbers are especially damning since Linux started with superior technology, has an easier business model if your only goal is market share, and did not have a legacy ball-and-chain anywhere near the size MS has to drag along. But years of directionless bloat have taken a toll and the sponsor driven decisions to go for traditional “server/OS” technology methods in place of trying to find solutions to current customer problems has been very damaging.

Even discounting the obvious PR froth of this article: http://www.eweek.com/c/a/Linux-and-Open-Source/Linux-Losing-Market-Share-to-Windows-Server it is an interesting trend.

and just for kicks from April 2000

“During his presentation on scaling Linux to the enterprise, BitMover, Inc. CEO Larry McVoy raised a few furrowed eyebrows at the recently-held Colorado Linux Info Quest (CLIQ). His message: Symetric multiprocessing (SMP) scaling may be hazardous to your operating system (OS) health.”

“McVoy said that the level of harm is “directly proportional” to the amount of scaling and is “worse than linear” in the number of processors. Converting a uniprocessor OS to a four-way SMP OS introduces a “small amount of damage.” Converting the four-way SMP OS to a 32-way SMP OS does even more damage, he told the crowd. McVoy calls this phenomenon “the locking cliff.””

“The bottom line, said McVoy, is that: “Linux needs to have bragging rights on ‘big iron’ to be taken seriously in the enterprise. But the traditional way of getting those rights involves a series of changes which do a lot of damage to the source base. So the problems are that Linux needs to scale, and traditional scaling is a bad idea. Linux will use traditional scaling if nothing else shows up,” he said, “but SMP clusters is a better way to do it. I’m the driving force behind that and I’m not driving because I’m wrapped up in BitKeeper.””

http://www.linuxtoday.com/news_story.php3?ltsn=2000-04-13-010-06-NW&tbovrmode=3

Categories
operating systems

Linux semaphores

Re: Schedule idle
MOLNAR Ingo (mingo@chiara.csoma.elte.hu)
Wed, 11 Nov 1998 04:09:32 +0100 (CET)
[…]
> _please_ We can do better than this. Only semaphores (not spinlocks) need
> to have the priority inheritance. […]
nope there are _not_ only semaphores, but many other types of locks.
> […] This can be done with lists off the
> semaphore and tasks… […]
it’s _not_ easy to extend Linux semaphores to handle priority inheritance. currently semaphore operations can be done via hw-atomic test-and-set instructions. If we do anything more complex, we cannot use simple instructions anymore. Linux semaphores are 2 instructions for an up() and 2 for a down(), and thats one of our crown jewels :)

the whole point is not quite valid, RT and filesystem IO doesnt mix well anyway … the solution: use system calls that are guaranteed to not block, either by design, or by system policy (ie. separate filesystem on a RAMDISK) … or use a device that doesnt introduce large latencies. (RAMdisk or solid state disk)

And then ….



		
Categories
operating systems

New paper “H2” on operating system semantics

Please see a new version here. I am continuing to try to develop a practical engineering mathematics for operating system and other complex system code.

Categories
software business

end to end design versus BOM design

Grossly simplifying, some products are Bill of Materials (BOM) products and some are Designed products. BOM products come to market via a process of generating a parts list and then integrating. In place of designers, BOM products have buyers and integrators. In place of innovation, BOM products have standards. The standards are preferably “industry standards” produced by consortia of companies that manufacture or distribute the product. Vendors compete on price and “alliance” to be allowed to sell parts to the integrators. Buyers work in a bureaucratic system in which specialists oversee acquisition of parts and the product as a whole is viewed primarily in terms of the sum of parts costs. Usually there are a small number of large integrators who act as the gateway to the market.

All the recent progress in cell phone handsets has come from companies that defied the BOM process. Instead of trying to sell items into the “stack”, RIM and Apple both have been able to imagine the handset as a complete product and innovate. Google is also changing the game by bearing down on what services can be delivered over a mobile device. These companies are in the business of creating products for end users and not in the business of selling parts to buyers of components. If you create products, BOM issues don’t go away, but they do not dominate.

The BOM process can dominate even in what appear to be more open markets. In a previous note, I discussed Dell’s efforts to sell against Apple to the people and businesses found at SXSW. Even though, as Jay Pinkert points out, Dell has improved design for cases, it labors under a disadvantage against Apple, because Apple can do end-to-end product design and Dell is forced to live at least in part in the BOM process world. Apple is not only designing the case, they control the operating system, the windowing environment, the middleware, and they can strongly influence and package application software. So Apple can look at what a conference organizer or musician wants or maybe what they will want once someone shows it to them, and try to design a product that will be compelling in totality. A company like Dell is constrained to delivering what is ultimately just a vehicle for vanilla Windows (or Linux) – a component of a stack. While the packaging can be improved, they cannot reach the customer in the same way that Apple can. Musicians and conference organizers and marketing agents want to have an aesthetically pleasing communications/graphics design machine or email/composing system or presentation device or some combination of these. None of them demand Vista or OS/10 or an intel processor or any of the technical parts. Of course, the traditional downfall of companies like Apple is that they grow an internal BOM process that transforms their own engineering staff into integrators and parts vendors.