Not only are the class files (from core java) memmaped into the process but I believe that they are also pre verified (verification of class files takes a significant proportion of the time required to load class files). I think this has been added in Sun java 1.6 as well (thanks to apple).
The server options do perform far more agressive optimizations under the assumption the the code will run for far longer then normal client apps (it can afford the extra overhead of the optimizations as they are offset over a longer period of time). It is a bit wierd watching your server get faster over time and often not particularly desirable for servers (you often want them pretty fast from the get go) so you have the option of increased startup cost and its corresponding increased performance from startup.
There has been talk about caching the compiled code but I don't think it has happened yet. One of the complications is that Java has the ability to dynamically load new code at runtime. This means that hotspot has to be able to back-out any optimisations it has made if newly loaded classes make them incorrect.
Java also has pretty good version handling of packages however it is often not used correctly. OSGi can help with this and provide many other benifits.
Actually hotspot compiles code after it has been interpreted for a while and it has noticed that it is a "hotspot" in the code (sort of there in the name really). The slow start up is because a) it loads and validates a fuck load of classes at startup (although the preverified core classes can be cached) b) it starts running in interpreted mode.
Now multiply that by about 2.5 to account for the cooling, and add in a few mil for the building to put it in + a bit more for some people to run it + a bit more for the people to develop the apps for it and you are about set.
So yes the electricity bill is huge but only about the same cost as one of the people you employ to use it.
I believe this series is changing its rules to handicap diesel cars.
Most of this has been achieved because they can manufacture lightweight diesel engines that can withstand the higher ignition pressure wrt petrol cars. This means the engine weighs about the same as a petrol engine but has more torque and greater engery density for its fuel (less fuel less weight)
BSD allows relicensing under pretty much any other license so long as it is also licensed under BSD. You are not allowed to remove the copyright from the files.
The role of JAI is to process images NOT to load/store them. It had a number of unsupported codecs for loading images because there was no decent framework in java to do so at the time. They probably should have used JIMI to loaded/store images but they did not for some reason. ImageIO was developed in parallel with JAI (actaully a bit behind).
JAI is still in use. It is still supported (apart from the com.sun* image codecs it originally had). It is complicated to use. It is very powerful.
I think he may be refering to the 10's to 100's of thousands of tonnes of radioactive steal, concreate and other materials that where the reactor. Although this doesn't get shiped to third world countries as we tend to leave it where it is, stick a concrete block on top of it and hope for the best.
P.S. I'm not particularly in favour of subsidies/tariffs but your last paragraph seems to assume that nothing can disrupt the global economy to the extent of food shortages when we have at least two major examples of exactly that occuring in the last one hundred years.
You can use independent component analysis to pull out up to N independent signal sources if you have N mics. Note that first you would have to account for time delays although these are not likely to be significant for a group of people talking to each other.
GSM mobile phones have a very accurate internal time signal. They need this to be able to broadcast in their allocated slots (not sure about CDMA). Timestamping recorded data should give you sufficient accuracy to remove any delays if they are not insignificant in the first place.
wisdom teeth are often very dangerous. Most people who have them removed have it done for medical reasons (in the UK anyway). Impacted teeth cause infections and without antibiotics these can easily kill you. I had mine removed after the third infection within a year (at about 21).
For anybody needing thier wisdoms removed I would have to recomend having done under local anesthetic. Its an unpleseant experiance but you come out of it with no bruseing, no dislocated jaw, no black eyes and can go to the pub the same day.
A significant number of the recent bombings (spain, england) have been performed by people from those countries. That pretty much rules out the "orign country" as a significant factor. Religion becomes insignificant if you look at the profile of terroists over that past 30 years. Many have been Caths, Prots, muslim, no-particular-religion (ireland (IRA, PLA), spain (basque speratists), bali (islamists (probably), even pro-lifers). They may not have killed as many people as the event in Sept 11th but as a proportion of population they are probably higher. Then there are women who seem to be quite willing to kill themseles for what ever cause they have (see palestine at the moment) suggesting that "men" is not a good indicator.
So none of the indicators you gave actually provide any real information. Each indicatior includes a huge proportion of the worlds population. Combining them does not reduce the number of potential suspects, it increases the number of partial matches and emphasises those who match all the crteria.
You would have no chance if you were a Hermaphrodite who lived in numerous countries and changes thier religion regularly.
You do get to use all the ram in the machine. Its just that a single process cannot access more then 4 Gig of address space (of which 1 or 2 gig is reserved for the OS). So a single process is limited but all your processes are not.
The popularity of SMS has little to do with the cost. You can generally talk to someone for a few mins on a mobile phone for the cost of sending an SMS.
depends on whether the plane is inherently satble, neutral, or unstable.
High wing planes (often stable) tend to level out. Although thier final course won't be the same as the original it will stop changing. neutral planes tend to carry on turning at the same rate. unstable planes (often low wings) tend to more and more extreme rates of course change (and end up buried in the groung without intervention).
There is no real "plane" analogy for "returning to course" (unless you have an autopilot)
The earth has been known to go through vast changes in the past. It always seems to return to some kind of heading. The question is whether we can wihstand the G forces involved in the turn.
Does pair programming not involve 2 people? Or do you just not pair programming when the task is boring? Or is refactoring not thought to be programming?
It would take about 2 mins to describe the goal of the refactoring. It took two weeks to do it. There was no creativity involved just lots of button pushing to tell an IDE what to move where. A second person could not contribute (unless they could use a seperate machine). Therefore they would
have nothing to do but "peer over my shoulder" for two weeks (while of course being completely amazed at my ability to push buttons rapidly and the pretty effects that appearing and disapearing popups have).
I've just spent the last two weeks refactoring a piece of code. It bored me senseless. I could not imagine how it would have felt for someone looking over my shoulder. Wooo. Two whole weeks of stareing at someone using an IDE to push exceptions through to all interfaces, delegates and implementations of those methods affected by each and every change. Great use of time that would be.
However I also know that code reviews (after the fact) start to fail when a code change is large (as with the rafactoring mentioned above). Nobody can read the code changes for a large body of work and KNOW that they will work. There are just too many assumptions in the code, and too large a scope for anybody to be able to understand the new code. They most definately cannot judge it for correctness (which they possibly could using pair programming). At this point code reviews tend to degrade to analysis of specific problems but do not provide any real help with respect to overall functionality of the code. Code reviews (after the fact) can ensure that the correct "appraoch" was taken and that specifics of the code were correct but that only happens if the reviewer has intimate knowlege of the code being chaneged.
I'm not really sure what my point is.
The only thing I know is that all processes fail at some point. In software engineering that point (failure of process) occurs far to often for comfort.
The comparison was a blind test between bell wire (often used to wire your door bell) and some very high end interconnects. The panel of judges were audiophiles. The results suggested that they could all tell the difference between the two. However there was approximately a 50/50 split as to which cable was prefered.
very easy. Executables can contain arbitrary data. You just have to make sure the execution path does not take you into it. static data such as icons are often stored in executables.
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Embedded C/C++ also hide many of the details. Why arn't you writing in assembly?
i ndex.jsp
e ssor&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB: official&client=firefox-a
Joking aside, Java is making inroads into embedded realtime systems.
http://java.sun.com/javase/technologies/realtime/
Thats not counting the processors available that have java bytecode as thier native instruction set.
http://www.google.co.uk/search?q=native+java+proc
matfud
Not only are the class files (from core java) memmaped into the process but I believe that they are also pre verified (verification of class files takes a significant proportion of the time required to load class files). I think this has been added in Sun java 1.6 as well (thanks to apple).
matfud
The server options do perform far more agressive optimizations under the assumption the the code will run for far longer then normal client apps (it can afford the extra overhead of the optimizations as they are offset over a longer period of time). It is a bit wierd watching your server get faster over time and often not particularly desirable for servers (you often want them pretty fast from the get go) so you have the option of increased startup cost and its corresponding increased performance from startup.
There has been talk about caching the compiled code but I don't think it has happened yet. One of the complications is that Java has the ability to dynamically load new code at runtime. This means that hotspot has to be able to back-out any optimisations it has made if newly loaded classes make them incorrect.
Java also has pretty good version handling of packages however it is often not used correctly. OSGi can help with this and provide many other benifits.
matfud
Actually hotspot compiles code after it has been interpreted for a while and it has noticed that it is a "hotspot" in the code (sort of there in the name really). The slow start up is because
a) it loads and validates a fuck load of classes at startup (although the preverified core classes can be cached)
b) it starts running in interpreted mode.
matfud
Now multiply that by about 2.5 to account for the cooling, and add in a few mil for the building to put it in + a bit more for some people to run it + a bit more for the people to develop the apps for it and you are about set.
So yes the electricity bill is huge but only about the same cost as one of the people you employ to use it.
diesel race cars are a bit rare but they do exist and do very well
0 .stm
http://news.bbc.co.uk/sport1/hi/motorsport/482236
I believe this series is changing its rules to handicap diesel cars.
Most of this has been achieved because they can manufacture lightweight diesel engines that can withstand the higher ignition pressure wrt petrol cars. This means the engine weighs about the same as a petrol engine but has more torque and greater engery density for its fuel (less fuel less weight)
matfud
BSD allows relicensing under pretty much any other license so long as it is also licensed under BSD. You are not allowed to remove the copyright from the files.
The role of JAI is to process images NOT to load/store them. It had a number of unsupported codecs for loading images because there was no decent framework in java to do so at the time. They probably should have used JIMI to loaded/store images but they did not for some reason. ImageIO was developed in parallel with JAI (actaully a bit behind).
JAI is still in use. It is still supported (apart from the com.sun* image codecs it originally had). It is complicated to use. It is very powerful.
matfud
Nasa just released a java (jogl) version of world wind (well an SDK for obtaining and rendering the data). Thought it might interest you.
http://worldwind.arc.nasa.gov/java/index.html
matfud
quite possibly
. pdf
http://www.ryansutherland.com/media/tetrachromats
matfud
I think he may be refering to the 10's to 100's of thousands of tonnes of radioactive steal, concreate and other materials that where the reactor. Although this doesn't get shiped to third world countries as we tend to leave it where it is, stick a concrete block on top of it and hope for the best.
Why not try the backport of the concurrency package http://dcl.mathcs.emory.edu/util/backport-util-con current/
P.S. I'm not particularly in favour of subsidies/tariffs but your last paragraph seems to assume that nothing can disrupt the global economy to the extent of food shortages when we have at least two major examples of exactly that occuring in the last one hundred years.
Try the always popular "yet another world war". Humm, yes food is still being produced but unfortunately you can't ship it.
Jikes is a compiler. It IS much faster then javac. Neither have much to do with runtime performance which is where hotspot is used.
Hotspot optimises code at runtime not at compile time. If you compile code using jikes then it wil still be optimised by the JVM at runtime.
So what exactly are you talking about
You can use independent component analysis to pull out up to N independent signal sources if you have N mics. Note that first you would have to account for time delays although these are not likely to be significant for a group of people talking to each other.
GSM mobile phones have a very accurate internal time signal. They need this to be able to broadcast in their allocated slots (not sure about CDMA). Timestamping recorded data should give you sufficient accuracy to remove any delays if they are not insignificant in the first place.
matfud
wisdom teeth are often very dangerous. Most people who have them removed have it done for medical reasons (in the UK anyway). Impacted teeth cause infections and without antibiotics these can easily kill you. I had mine removed after the third infection within a year (at about 21).
For anybody needing thier wisdoms removed I would have to recomend having done under local anesthetic. Its an unpleseant experiance but you come out of it with no bruseing, no dislocated jaw, no black eyes and can go to the pub the same day.
A significant number of the recent bombings (spain, england) have been performed by people
from those countries. That pretty much rules out the "orign country" as a significant factor.
Religion becomes insignificant if you look at the profile of terroists over that past 30
years. Many have been Caths, Prots, muslim, no-particular-religion (ireland (IRA, PLA), spain
(basque speratists), bali (islamists (probably), even pro-lifers). They may not have killed as many people
as the event in Sept 11th but as a proportion of population they are probably higher. Then
there are women who seem to be quite willing to kill themseles for what ever cause they have
(see palestine at the moment) suggesting that "men" is not a good indicator.
So none of the indicators you gave actually provide any real information. Each indicatior includes
a huge proportion of the worlds population. Combining them does not reduce the number of potential suspects, it increases the number of partial matches and emphasises those who match all the crteria.
You would have no chance if you were a Hermaphrodite who lived in numerous countries and changes thier religion regularly.
matfud
You do get to use all the ram in the machine. Its just that a single process cannot access more then 4 Gig of address space (of which 1 or 2 gig is reserved for the OS). So a single process is limited but all your processes are not.
The popularity of SMS has little to do with the cost. You can generally talk to someone for a few mins on a mobile phone for the cost of sending an SMS.
depends on whether the plane is inherently satble, neutral, or unstable.
High wing planes (often stable) tend to level out. Although thier final course won't be the same as the original it will stop changing.
neutral planes tend to carry on turning at the same rate.
unstable planes (often low wings) tend to more and more extreme rates of course change (and end up buried in the groung without intervention).
There is no real "plane" analogy for "returning to course" (unless you have an autopilot)
The earth has been known to go through vast changes in the past. It always seems to return to some kind of heading. The question is whether we can wihstand the G forces involved in the turn.
matfud
Does pair programming not involve 2 people? Or do you just not pair programming when the task is boring? Or is refactoring not thought to be programming?
It would take about 2 mins to describe the goal of the refactoring. It took two weeks to do it.
There was no creativity involved just lots of button pushing to tell an IDE what to move where. A
second person could not contribute (unless they could use a seperate machine). Therefore they would
have nothing to do but "peer over my shoulder" for two weeks (while of course being completely amazed
at my ability to push buttons rapidly and the pretty effects that appearing and disapearing popups have).
I have to agree.
I've just spent the last two weeks refactoring a piece of code. It bored me senseless. I could not imagine how it would have felt for someone looking over my shoulder. Wooo. Two whole weeks of stareing at someone using an IDE to push exceptions through to all interfaces, delegates and implementations of those methods affected by each and every change. Great use of time that would be.
However I also know that code reviews (after the fact) start to fail when a code change is large (as with the rafactoring mentioned above). Nobody can read the code changes for a large body of work and KNOW that they will work. There are just too many assumptions in the code, and too large a scope for anybody to be able to understand the new code. They most definately cannot judge it for correctness (which they possibly could using pair programming). At this point code reviews tend to degrade to analysis of specific problems but do not provide any real help with respect to overall functionality of the code. Code reviews (after the fact) can ensure that the correct "appraoch" was taken and that specifics of the code were correct but that only happens if the reviewer has intimate knowlege of the code being chaneged.
I'm not really sure what my point is.
The only thing I know is that all processes fail at some point. In software engineering that point (failure of process) occurs far to often for comfort.
matfud
It has been done.
The comparison was a blind test between bell wire (often used to wire your door bell) and some very high end interconnects. The panel of judges were audiophiles. The results suggested that they could all tell the difference between the two. However there was approximately a 50/50 split as to which cable was prefered.
matfud
I think it was the "which" magazine in the uk.
very easy. Executables can contain arbitrary data. You just have to make sure the execution path does not take you into it. static data such as icons are often stored in executables.