A sysadmin I knew had an old machine dedicated to logging set up in a broom closet, printing out the important log messages on a dot matrix printer fed by a box of continuous folded paper.
And without that tech, how are you going make new photovoltaic cells ?
Solar thermal.
Solar thermal only provides you with raw energy, not the extremely fine tuned equipment to make pure silicon crystals. And every step of the way requires other specialized equipment of materials. Right now, a factory in Taiwan can simply order a $3 widget from a Swiss factory catalog that takes raw materials from Australia and Brazil. Without that supply network, obtaining simple things like that become nearly impossible. And don't forget that without somebody else taking care of basic needs (food, water, shelter), the typical engineer won't be sitting behind a desk thinking about ways to replace this $3 widget. They'll be hunting the streets for food, and looting the lab for blunt objects they can use to protect their family at home.
However it is also not necessarily true that the current panels would not last long enough to give that sort of boost to get new ones made.
They most likely wouldn't last long enough. After the initial collapse, the society would keep falling more and more, as people plunder whatever is left in a daily struggle for basic needs. The population would need to be reduced by several orders of magnitude, before there's any chance of stabilization and actual rebooting. By that time, most of the tech factories, knowledge, infrastructure, and useful materials will be destroyed.
And it'll be easier than starting from scratch due to all the tech we'll have lying around.
If you assume that all our high tech factories will still be operational, that's hardly a reboot. And without that tech, how are you going make new photovoltaic cells ?
Early fossil fuels, when our society first starting using them, were basically free. Oil was seeping out at the surface layers, and good quality coal was easy to reach.
After a reboot, the remaining oil will be so well hidden, and so expensive to exploit, that it will probably never happen.
Who cares that solar panels only can convert about 10-15% of the power it receives now
That's not the issue. The problem is that solar panels deteriorate over time, and that a collapsed society doesn't have the technological means to build new ones.
When I went to school in the 80's, both my physics and chemistry teachers had a PhD. I remember my physics teacher deriving the formula for centripetal force on the blackboard from basic concepts, without using calculus. I don't think many of today's teachers would even know where to start.
The major problem is not the performance of the CPU.
To pass a message across a protected barrier, it means that you can't use two references to the same data. You must actually make a copy of the data. Everybody thinks that the time spent making the copy is a problem with microkernels that needs to be addressed. But the real problem is not the time to make a copy. The real problem is that you now have two different copies of the same data. And when you modify one copy of the data, to update some of the state, the other copy remains in the old state, which is generally not a good idea, unless you have carefully made a design that can tolerate such differences. Or, you would have to build in frequent synchronisation points where all the new state information is distributed to all the tasks. This means poor performance, because the tasks will spend a lot of time waiting for other tasks to catch up.
So, using the same line of thinking, they are also promoting hiring more male teachers to properly educate the boys in the classroom ? The elementary school that my kids went to saw their last male teacher leave a few years ago.
I wouldn't say minix is a good example here, performance wise, as it's intended primarily to be an educational tool.
Still, it's worthwhile to examine the problems, and think about how to solve them. Minix has a clear and serious problem with the single threaded filesystem, and its lack of performance. If you want to scale it up to a general purpose computer system (not a small embedded, single purpose design), you're either going to have to a) keep it as a single task but make it smarter, or b) split it up in multiple tasks. Keeping a filesystem as a single task is problematic. For instance, a request comes in that requires waiting for physical hardware. While the task is waiting, other requests come in that can be served from the cache, but since the task is waiting for the hardware, these requests will have to wait, wasting performance. Trying to fix that by building giant state machines makes a huge mess out of the design. On the other hand, trying to improve performance with multiple, independent, threads basically turns the filesystem into a distributed filesystem, with all the synchronisation issues.
In a monolithic kernel, none of these problems exist. Every application request that enters the filesystem layer automatically continues in its own independent thread. When it hits an area that requires synchronisation, it briefly acquires a lock (usually without contention), does the work, and releases the lock. This is a much simpler design, with higher performance.
Yet 100 times smaller cellphone has a need for 4K....
5.5 inch phone is only 18 times smaller than a 100 inch TV, and watching your phone from 5 inch away is about equivalent to watching the big TV at 8 feet. So, 4K on a phone is in the same ballpark as 4K on a big screen TV.
No, micro kernels are plain worse. The biggest problem with micro kernels is the synchronisation problem you get with distributed state. Imagine a file system that is split up in different tasks, instead of one monolithic blob. Now, one task makes a change, like removing a file. Before the other tasks can make changes to the filesystem, they first need to synchronize to get the latest state. This becomes either terribly inefficient, or a huge mess, and most likely both at the same time.
Minix, for example, solved this particular problem by letting the entire filesystem be supported by a single task, but results in terrible scaling performance when adding more users/processes.
The test cars that are on the road seem to be doing pretty well. I wouldn't be surprised if they've already surpassed human drivers for the easy roads.
Slashdot Mirror
http://en.wikipedia.org/wiki/1980_Pennsylvania_Lottery_scandal
You could fix the ball machine and its procedures easier than you can get a computer to function properly.
Also called: torture the data until it confesses.
A sysadmin I knew had an old machine dedicated to logging set up in a broom closet, printing out the important log messages on a dot matrix printer fed by a box of continuous folded paper.
And without that tech, how are you going make new photovoltaic cells ?
Solar thermal.
Solar thermal only provides you with raw energy, not the extremely fine tuned equipment to make pure silicon crystals. And every step of the way requires other specialized equipment of materials. Right now, a factory in Taiwan can simply order a $3 widget from a Swiss factory catalog that takes raw materials from Australia and Brazil. Without that supply network, obtaining simple things like that become nearly impossible. And don't forget that without somebody else taking care of basic needs (food, water, shelter), the typical engineer won't be sitting behind a desk thinking about ways to replace this $3 widget. They'll be hunting the streets for food, and looting the lab for blunt objects they can use to protect their family at home.
However it is also not necessarily true that the current panels would not last long enough to give that sort of boost to get new ones made.
They most likely wouldn't last long enough. After the initial collapse, the society would keep falling more and more, as people plunder whatever is left in a daily struggle for basic needs. The population would need to be reduced by several orders of magnitude, before there's any chance of stabilization and actual rebooting. By that time, most of the tech factories, knowledge, infrastructure, and useful materials will be destroyed.
Related. Here's a fun presentation from a guy trying to build a simple toaster from scratch.
https://www.youtube.com/watch?...
And it'll be easier than starting from scratch due to all the tech we'll have lying around.
If you assume that all our high tech factories will still be operational, that's hardly a reboot. And without that tech, how are you going make new photovoltaic cells ?
Early fossil fuels, when our society first starting using them, were basically free. Oil was seeping out at the surface layers, and good quality coal was easy to reach.
After a reboot, the remaining oil will be so well hidden, and so expensive to exploit, that it will probably never happen.
so why would we need more than maintenance-level stocks of tar and asphalt?
Because people dig up the old asphalt roads so they can burn the tar to stay warm ?
Who cares that solar panels only can convert about 10-15% of the power it receives now
That's not the issue. The problem is that solar panels deteriorate over time, and that a collapsed society doesn't have the technological means to build new ones.
When I went to school in the 80's, both my physics and chemistry teachers had a PhD. I remember my physics teacher deriving the formula for centripetal force on the blackboard from basic concepts, without using calculus. I don't think many of today's teachers would even know where to start.
I'm waiting for Intel to integrate systemd in the next core update.
The major problem is not the performance of the CPU.
To pass a message across a protected barrier, it means that you can't use two references to the same data. You must actually make a copy of the data. Everybody thinks that the time spent making the copy is a problem with microkernels that needs to be addressed. But the real problem is not the time to make a copy. The real problem is that you now have two different copies of the same data. And when you modify one copy of the data, to update some of the state, the other copy remains in the old state, which is generally not a good idea, unless you have carefully made a design that can tolerate such differences. Or, you would have to build in frequent synchronisation points where all the new state information is distributed to all the tasks. This means poor performance, because the tasks will spend a lot of time waiting for other tasks to catch up.
So, using the same line of thinking, they are also promoting hiring more male teachers to properly educate the boys in the classroom ? The elementary school that my kids went to saw their last male teacher leave a few years ago.
I wouldn't say minix is a good example here, performance wise, as it's intended primarily to be an educational tool.
Still, it's worthwhile to examine the problems, and think about how to solve them. Minix has a clear and serious problem with the single threaded filesystem, and its lack of performance. If you want to scale it up to a general purpose computer system (not a small embedded, single purpose design), you're either going to have to a) keep it as a single task but make it smarter, or b) split it up in multiple tasks. Keeping a filesystem as a single task is problematic. For instance, a request comes in that requires waiting for physical hardware. While the task is waiting, other requests come in that can be served from the cache, but since the task is waiting for the hardware, these requests will have to wait, wasting performance. Trying to fix that by building giant state machines makes a huge mess out of the design. On the other hand, trying to improve performance with multiple, independent, threads basically turns the filesystem into a distributed filesystem, with all the synchronisation issues.
In a monolithic kernel, none of these problems exist. Every application request that enters the filesystem layer automatically continues in its own independent thread. When it hits an area that requires synchronisation, it briefly acquires a lock (usually without contention), does the work, and releases the lock. This is a much simpler design, with higher performance.
Yet 100 times smaller cellphone has a need for 4K....
5.5 inch phone is only 18 times smaller than a 100 inch TV, and watching your phone from 5 inch away is about equivalent to watching the big TV at 8 feet. So, 4K on a phone is in the same ballpark as 4K on a big screen TV.
Micro kernel is not necessarily better.
No, micro kernels are plain worse. The biggest problem with micro kernels is the synchronisation problem you get with distributed state. Imagine a file system that is split up in different tasks, instead of one monolithic blob. Now, one task makes a change, like removing a file. Before the other tasks can make changes to the filesystem, they first need to synchronize to get the latest state. This becomes either terribly inefficient, or a huge mess, and most likely both at the same time.
Minix, for example, solved this particular problem by letting the entire filesystem be supported by a single task, but results in terrible scaling performance when adding more users/processes.
Of course, as soon as you started with tapes from others, you entered the eternal process of turning the alignment screw on the recorder head.
Anyone who wears pants is an idiot.
I need them to hold my smartphone.
Most home computers from that era had cassette recorders.
The test cars that are on the road seem to be doing pretty well. I wouldn't be surprised if they've already surpassed human drivers for the easy roads.
Self driving cars only need to make less errors than smartphone-distracted humans. That's not a very high standard.
Fast cars, pretty women, and explosions is where the real money is at. Ingmar Bergman? Not so much.
There's quite an entertaining spectrum between those two extremes.
The "new" meaning (an individual that's deliberately abusive or deliberately fans the flames)
Actually, the new meaning is: someone who holds an unpopular opinion.
Nice try, troll.
http://en.wikipedia.org/wiki/T...