Robert Pogson

One man, closing all the windows.

Daily Archives / Sunday, October 23, 2011

  • Oct 23 / 2011
  • 3
technology

The Beast is Back

I finally installed the new motherboard for Beast. It’s a different chipset but the same CPU and RAM. As expected, GNU/Linux booted from the stock Debian kernel on the first go. I did have to reset the MAC address in my router to give Beast the correct IP address and that was it. I did not even have to worry about which drive was which because they all were identified by UUID. The hard part was getting the damned big hair-drying heat sink attached. My fingers are way too big and my eyes too poor for that kind of work. I was a millimetre or so away from having to remove the PSU to give my fingers more room.

Now I can boot virtual machines in a few seconds and test out all kinds of neat stuff. I have enough RAM for a whole cluster of virtual machines. I spent most of the day fiddling with Beast. It took hours to bring my local repository up to date. In the meantime I cleaned out obsolete files (like openoffice.org and .iso files I don’t need). Since it looks like Beast and I are now officially retired or soon will be, I can embed Beast into the home network a bit, making each client update from Beast and setting up backups of users’ files.

Beast feels really fast. With 3 hard drives it can really seek files much quicker than the notebook with its 2.5 inch drives and less powerful processor. LibreOffice opens in about 1s.

I am getting ready to hunt deer for the first time since 1996. In the North hunting is almost always done from vehicles and I did not have one up there so I have only hunted a couple of times in the years I was teaching in the North. Yesterday my son had a go with a deer rifle and experienced recoil… He fired a few 180 grain bullets from a .308 Winchester and found it accurate enough for gophers. Deer should be a piece of cake. We tried some 220 grain bullets but they did not stabilize in that rifle barrel. Tomorrow muzzle-loading season begins for three weeks. Since muzzle-loading is much less popular than centre-fire, we should have the bush to ourselves when we go out. The big problem will be finding space in the freezer with all those turkeys and vegetables… We might have to buy another freezer if hunting is successful.

  • Oct 23 / 2011
  • 4
technology

Web Applications

I love web applications. They allow me to stay in my nice, comfortable, tweaked web browser and do amazing things. Today, I visited http://orbit.homedepot.com/planner and planned an underground sprinkler system for my lot. It worked pretty well. The application combined my specifications of the lot, landscaping, water supply and buildings with the company’s database of components to produce a viable plan for irrigation for $7700 in parts.

That’s a bit high, so I refined it manually. I changed the selection of sprinklers to one kind only, the most efficient pop-up impact sprinkler and changed coverage so I would only overlap a maximum of two sprinkler heads on any part of the property. The automated plan had up to 3 heads watering each spot which is better, more uniform coverage, but the cost is far more than the benefit IMHO. I also simplified the control system, centralizing everything. This dropped the total cost of material to about $1500 making it more attractive.

The web application distributed sprinklers on the property line and every so many feet. That works but, I know from experience that the impact sprinklers scatter water for several feet opposite the stream so you can place them back from the property line. I also know that the trees my wife wants near the property line are “tower poplars” which are somewhat sparse lower down, so I can safely place the trees a few feet from the property line and place a line of sprinkler heads a few feet inside that, shrinking the size of the lot needing coverage. I can also set the sprinklers to about 190 degrees of coverage at the edges to water the line of trees very well. These trees tolerate drought anyway.

By using fewer sprinklers, I can greatly reduce the piping, solenoid valves and cable in the system. The impact sprinklers are much more efficient than continuous sprayers. The impact sprinklers I use now can cover a 70 foot diameter of circle, so a few of them covers the width of the yard with partial overlap. Orbit wants to have each sprinkler head spray the next head but by using just 10 feet of overlap, I can cut the cost of the project way down and everyone gets water. Instead of watering uniformly, I can mow uniformly. My water is also cheap so I can overwater. It all works.

Here’s a guy who has a cheaper DIY design. His cost was also about 4 times less than “standard” just by using the most efficient coverage and tolerating a few gaps.

I don’t dispute that the Orbit planner would produce a better design but for a little better performance, I would be paying several times a larger cost. Also the maintenance of the system would be much larger with more moving parts. Installation will be several times less with my design. The Orbit design called for two miles of pipe. I can do it for about 1/3 of a mile, and since I am the source of labour, that decides it for me. Now to consult with the little woman…

I think this example is indicative of some differences between FLOSS and “commercial” software. FLOSS may leave some gaps but it is far more efficient use of IT. There are always work-arounds for gaps but money/effort once spent is usually gone with non-free software but the effort spent to cover a gap in FLOSS is available for re-use. Both systems get the job done but the costs can be much different. FLOSS also tends to give better performance because it is not trying to do all things for everyone in a particular application. Orbit’s application, no doubt, works for many but it is not optimal for everyone. I could pay the money, hire workers and have Orbit’s plan implemented next week. I can pay a lot less and have my system installed by me eventually. If I have complete control of the design and implementation I can also maintain it more easily. I prefer my way.