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Comment Re:And what's wrong with such reasonable assumptio (Score 2, Informative) 358

In some cases, because people in management justify their existence (and salaries) by the number of people that report to them. Add more employees, manager's importance goes up. That provides a strong incentive to have employees that don't do anything useful, but do report to you.

Comment Re:Get a cheap PC that 10 years old, add PFSense (Score 1) 316

I'm not sure if your unit is correct... I am quite sure that you meant £1 per kWh (Kilo Watt Hour) per year.

£1 per Watt for one year. Rough estimate, but it's in the right ballpark. I pay 12p/kWh. That's £0.00012 for 1W for one hour. For one day, it costs £0.00288. For 365 days, it costs £1.0512, so an estimate of £1/Wyear is only 5% off. The unit of kWh per year wouldn't make sense: Watts are a unit of power (energy per unit time). 1kWh is one kW (1000W) for one hour. i.e. my price of £0.12/kWh means that it costs £0.12 to have something that draws 1kW on for one hour (or to have something that draws 100W on for ten hours, and so on). I probably should have written £1/Wyear for consistency with kWh or £1/(W/year), but I assumed that readers could figure it out and was lazy.

A 6 wH router would require 52.56 kW to operate in a year (24/7 and 365 days a year)... So, I don't get the part where you are talking about saving. :-?

What is a 6wH router? Even if you mean 6Wh, that doesn't make sense: how long does it take to consume 1Wh (a unit of energy, not of power)? If you mean a 6W router, then will consume 52.56Wh in one year (not 52.56kW, because that's a unit of power and when you divide by time [i.e. over a year] then you get energy, not power). In contrast, a 60W old PC will consume 525.6kWh. At £0.12/kWh, that works out at £6.3072 to operate the small router or £63.072 to operate the old PC for one year. These numbers are very close to my back-of-an-envelope estimate of £6 vs £60, but more accurately the saving is £56.7648/year, or £113.5296 over two years. If you spend £100 on a low-power embedded router board to replace a 60W old PC that you got for free then you will be £13.5296 better off after two years (assuming electricity prices don't go up and you're on the same-priced tariff as me). After four years, you'll be over £100 better off. The one that I bought lasted 5 years before it was too slow for the network, so that's a saving of £283.824 of electricity. The new version of the same board (three gigE ethernet adaptors and enough CPU power to happily handle line rate on all of them) costs £125, probably around £160 by the time that you've added a case and some flash storage. So over the lifetime of the device (assuming it only lasts five years - I'd actually be quite surprised if GigE is not fast enough in 5 years for most home users), the saving is around £120, more if electricity prices go up. The break-even point is just over two years. As an added bonus, you get a small form-factor device that's silent, so can be hidden in a corner in a room that you actually use, or stored in an under-stairs cupboard without overheating.

Using an old PC for this is likely to be a waste of money and be inconvenient. If you can get £20 for the old PC from someone who actually needs a machine capable of running a GUI, then you're even better off!

Comment Re:Paintbrush for Windows (Score 1) 378

Nope. Paintbrush, which shipped with Windows up until 3.11 was a bundled version of ZSoft Paintbrush, with a few features removed and Microsoft branding on top. MS Paint, introduced with Windows 95 (I think, possibly NT 3.x?), was a complete rewrite as a win32 app. The author of TFA doesn't know what he's talking about - it most certainly hasn't been part of Windows since 1985.

Comment Re:Get a cheap PC that 10 years old, add PFSense (Score 3, Informative) 316

You can't do arithmetic: 24 * 365 * 100 = 876000. 24 * 365 * 100 / 1000 = 876. Your 87600 is neither of these numbers and I have no idea how you calculated it. The rough rule of thumb is $1/W/year, with your price estimate it's $1.0512, which is close enough. With 18 cents/kWh, it's $1.5768, but for most of the US $1-2 is the right ballpark. For Germany, it's $3. That doesn't actually detract too much from your main point. You're paying $300/year for power for the 100W machine. A 6W machine that costs $200 will save you over $90 in the first year.

Comment Re:Get a cheap PC that 10 years old, add PFSense (Score 4, Informative) 316

Power here costs about £1/W/year. If you're expecting to keep your router for 2 years, it's worth spending up to £20 to reduce the power consumption by 10W. A typical old desktop will draw around 60W, an embedded router board will draw around 6W. That works out at a saving of £108 over two years, which is about the total cost of the embedded router board (PC-Engines or Soekris). After three years, even if you got the old PC for free, it's still more expensive. I used a PC-Engines WRAP board as my home router for around 5 years before needing to upgrade.

Comment Re:Another bubble. (Score 1) 370

I can't speak for Facebook, as I don't work with them, but most of the people I collaborate with at Google, Microsoft and Apple are over 40, many over 50. And a few of them have been headhunted by these companies very recently (quite a few are former HP or Sun folk). All of these companies are very happy to hire competent older people. They're not; however, happy to keep increasing a salary for someone who has managed to gain age without gaining experience.

Comment Re:What does this do that Java does not? (Score 1) 370

The article you link to is about introspection, which is a subset of reflection. With introspection, you can do things like ask what methods an object implements or what fields it has. With reflection, you can do things like replace the implementation of a method at run time. Languages that actually support reflection often integrate it in core ways with the core frameworks. For example, one of the common design patterns in Cocoa is Key-Value Observing, where you register to receive events when a property of an object changes. If you are assigning to instance variables of an object directly, then you need to call some helpers to make this work, but if you use the normal accessors then the framework makes it automatic, by replacing the accessor with an implementation that fires the will-change notification, then calls the original implementation, and then fires the did-change notification. From the page that you linked to, I don't believe that you could implement this in Pascal.

Comment Re:I tried Python (Score 4, Informative) 370

There are a couple of reasons 0-based indexing makes sense. The first only really matters in low-level languages: the indexes represent the offset from the array. The address of array X and index 0 into array X are the same. The second relates to concatenating arrays. The place that you insert into the first array is the length of the array. This idiom crops up sufficiently often that zero-based indexing saves a surprising number of +1 calculations in a program - it's very common for programmers to accidentally clobber the last element in an array in languages that index from 1. Mathematics understands that cardinals and ordinals are different, but programmers often forget...

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