I personally believe that it's the individual's responsibility to stay up to date with developments in her area of expertise. However, it is crucial that employees who will be using or managing a system be properly trained in that task *before the system goes live*, and the most reliable means of ensuring that someone is properly trained is to put them through a course on the subject. Judgements about your employer aside, you should be able to make a very strong case for training, as your knowledge of this topic has a very measurable impact on network operation and reliability.
I suggest opening an email dialogue with the powers that be explaining the situation and suggesting training as the most efficient means of giving you the skills to perform your job adequately. Then, if your are refused training you will have documented evidence that your lack of training was not a matter of your own negligence if something breaks and you have irate managers to deal with. And no matter what happens, I suggest reading up on the topic. On company time, if possible.
But, what has this got to do with the tcp connection? Not much.
Agreed. But the topic of his article is "Boost socket performance on Linux," not "How to optimize TCP layer use on Linux." And the article deals almost entirely with API-level settings. It just seems odd to me that he'd not mention issues with some of the classic BSD functions.
That is true, but only under workloads where one process has a lot of sockets open. A (somewhat old) article on this subject is here [kegel.com]. True enough. But how many applications nowadays are written expecting no more than ~32 simultaneous connections?
There was a Boost library in the works to encapsulate all of this rather nicely, but I'm not sure if it ever made it out of beta. ACE is another option, though that tends to be overkill for some projects. I rolled my own class wrapper around this stuff, but then I enjoy library programming.
Tuning socket parameters is great and all, but the real performance problem with socket IO has to do with using select and poll. There are high-performance alternatives (which admittedly tend to vary from OS to OS) that are so far superior that I wouldn't even consider the default methods unless complete code portability were a crucial factor.
In order to understand how bees carry such heavy cargo, the researchers forced the bees to fly in a small chamber filled with a mixture of oxygen and helium that is less dense than regular air. This required the bees to work harder to stay aloft and gave the scientists a chance to observe their compensation mechanisms for the additional toil.
The bees made up for the extra work by stretching out their wing stroke amplitude but did not adjust wingbeat frequency.
Okay, so as load increases bees beat their wings harder, not faster. Seems reasonable. They're probably built in such a way as either to optimize efficiency at a specific frequency or perhaps they simply can't beat their wings at any other frequency for some structural reason.
"They work like racing cars," Altshuler said. "Racing cars can reach higher revolutions per minute but enable the driver to go faster in higher gear. But like honeybees, they are inefficient."
So why is this design inefficient? The bee may perform more work per wing beat, but shouldn't it perform the same work per unit of time? And what about the comparison to car transmissions? If higher RPMs were more efficient wouldn't cars be designed differently? Also, if this design is inefficient, why would we model hovering planes after it? We've already got helicopters, after all.
Joke aside, it's always been a variable. It changes depending on the medium it's traveling through. 'c' is just the speed of light in a vacuum.
Technically, 'c' is the speed of light, period. The "slowing" effect has to do with the rate that photons are absorbed and re-transmitted by matter. The photons themselves always travel at 'c'. A small distinction perhaps, but an inportant one IMO.
It's one thing to play a copy of a Michael Jackson CD and enjoy it. It's another to play that CD for a friend and tell them you just recorded it in the studio. In the first case, Mr. Jackson is getting credit for having produced the music, and may be indirectly gaining fans (and therefore potential revenue) as a result. In the second, the artist is getting no credit for having created the material. This comparison roughly applies to software copyrights, though attributing the use of libraries with software typically requires the company's legal team and often adding stuff to documentation that no one wants there. I've had to avoid the use of some very popular free software before simply because legal refused to put the required blurb where it needed to be.
In short, decreasing the die size has allowed Intel to reduce power consumption a bit, but it's also increased thermal density to such a degree that they can't clock them as fast as even the current crop of 90nm processors. Why upgrade to these chips?
Re:mistake in the article
on
Homer Becomes Omar
·
· Score: 2, Informative
The article also says "Bart continues to bate his teachers." While 'bate' is a real word, I don't think it was intended in this case. Proofreading FTW!
in 212 BC, Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire.
If the enemy ships were anchored within bow and arrow range, I suspect that while Archimedes was fiddling with his mirrors, a few archers dipped their arrows in pitch and fired them at the fleet. Eventually, when Archimedes finished aiming his master weapon he was overjoyed to discover the fleet in flames. Archimedes reported his success to the king, and went down in history as the oldest recorded example of a horribly over-engineered solution to a simple problem.
that inspired my comment. The usability of both of these products is quite poor. It just happens that I find Blackboard slightly less annoying to use than WebCT.
For what it's worth, the criteria for this law are very similar to the FCC's profanity rules (through 1995 or so at any rate). The real problem in both cases is that everything is subjective and there is no formal review process in place to question uneducated rulings. Assuming games could be considered "art" or that a game may include content which is intended to provoke discussion, the possibility of hasty judgements resulting in 'improper' censorship are very real (assuming a store may not carry a game because it has an 'M' rating, which seems a reasonable assumption). For reference, this has happened with radio broadcasts from time to time (google "Sarah Jones" and "Your Revolution"), and the resulting mess took years to sort out--a time which could make or break a game company .
What exactly does this law hope to accomplish? Alcohol and cigarette laws make sense to a degree--a child can drink or smoke anywhere and both involve health risks. But games are typically played at home (where parents should be aware of the child's activities), and there are obviously no health risks involved. I half wonder if the movie industry lobbied for this law in order to regain viewership lost to video gaming.
I'm not sure I understand the logic behind your argument. Why is it necessary to eliminate technology simply because you don't know how to manage your free time in its presence? No one ever said that you have to answer the phone just because it's ringing. You can even turn the ringer off. How did this ever get to +5, insightful?
And the bulk of it is for bathing and the like. Amazing. I can understand this for established camps perhaps, but surely they don't bother with this on the front lines? If cleanliness is really that much of an issue, wipe down with a sponge. It'll take half a gallon of water and you'll end up almost as april fresh.
A soldier in the desert needs about 20 gallons of water a day, for all purposes
Unless "all purposes" includes taking a shower or using a flushing toilet I'm not sure I understand this estimate. A person in the desert needs to drink perhaps 1 gallon of water a day to stay sufficiently hydrated. Where does the other 19 gallons go?
and because of IP issues. The industry is resisting standardization to some degree because companies want to make money selling library code and the like. Personally, I relate software engineering today to pre-industrial tradework like blacksmithing. Most code for every project is written from the ground up and technical tricks are jealously guarded by many software houses (IP and non-compete laws now vs. less formal methods way back when). Eventually, however, the glory days will end as the average project size simply gets too large to be managed in such a manner. Particularly when software integrity becomes more of an issue. What will happen if the law changes such that all software must provide some stability and safety guarantees? As it is, things are abysmal. I've had to replace my last two cellphones (Motorola... never buying one again) because the firmware was garbage and they crashed and freaked out constantly. And cellphones are products that are expected to Just Work. What does that say about the rest of the industry? Calling the process an art is just a cop-out as far as I'm concerned. There's a difference between striving to build a flawless product and in embracing the flaws as a consequence of the artistic process--the latter group is just excusing their lack of skill or discipline.
Slashdot Mirror
Looks like it's about time to go home for the day.
I personally believe that it's the individual's responsibility to stay up to date with developments in her area of expertise. However, it is crucial that employees who will be using or managing a system be properly trained in that task *before the system goes live*, and the most reliable means of ensuring that someone is properly trained is to put them through a course on the subject. Judgements about your employer aside, you should be able to make a very strong case for training, as your knowledge of this topic has a very measurable impact on network operation and reliability.
I suggest opening an email dialogue with the powers that be explaining the situation and suggesting training as the most efficient means of giving you the skills to perform your job adequately. Then, if your are refused training you will have documented evidence that your lack of training was not a matter of your own negligence if something breaks and you have irate managers to deal with. And no matter what happens, I suggest reading up on the topic. On company time, if possible.
But, what has this got to do with the tcp connection? Not much.
Agreed. But the topic of his article is "Boost socket performance on Linux," not "How to optimize TCP layer use on Linux." And the article deals almost entirely with API-level settings. It just seems odd to me that he'd not mention issues with some of the classic BSD functions.
That is true, but only under workloads where one process has a lot of sockets open. A (somewhat old) article on this subject is here [kegel.com].
True enough. But how many applications nowadays are written expecting no more than ~32 simultaneous connections?
There was a Boost library in the works to encapsulate all of this rather nicely, but I'm not sure if it ever made it out of beta. ACE is another option, though that tends to be overkill for some projects. I rolled my own class wrapper around this stuff, but then I enjoy library programming.
Tuning socket parameters is great and all, but the real performance problem with socket IO has to do with using select and poll. There are high-performance alternatives (which admittedly tend to vary from OS to OS) that are so far superior that I wouldn't even consider the default methods unless complete code portability were a crucial factor.
Sounds like a good example of a horribly over-engineered solution to a simple problem. I'll just press the one button and wait, thanks.
In order to understand how bees carry such heavy cargo, the researchers forced the bees to fly in a small chamber filled with a mixture of oxygen and helium that is less dense than regular air. This required the bees to work harder to stay aloft and gave the scientists a chance to observe their compensation mechanisms for the additional toil.
The bees made up for the extra work by stretching out their wing stroke amplitude but did not adjust wingbeat frequency.
Okay, so as load increases bees beat their wings harder, not faster. Seems reasonable. They're probably built in such a way as either to optimize efficiency at a specific frequency or perhaps they simply can't beat their wings at any other frequency for some structural reason.
"They work like racing cars," Altshuler said. "Racing cars can reach higher revolutions per minute but enable the driver to go faster in higher gear. But like honeybees, they are inefficient."
So why is this design inefficient? The bee may perform more work per wing beat, but shouldn't it perform the same work per unit of time? And what about the comparison to car transmissions? If higher RPMs were more efficient wouldn't cars be designed differently? Also, if this design is inefficient, why would we model hovering planes after it? We've already got helicopters, after all.
Joke aside, it's always been a variable. It changes depending on the medium it's traveling through. 'c' is just the speed of light in a vacuum.
Technically, 'c' is the speed of light, period. The "slowing" effect has to do with the rate that photons are absorbed and re-transmitted by matter. The photons themselves always travel at 'c'. A small distinction perhaps, but an inportant one IMO.
It's one thing to play a copy of a Michael Jackson CD and enjoy it. It's another to play that CD for a friend and tell them you just recorded it in the studio. In the first case, Mr. Jackson is getting credit for having produced the music, and may be indirectly gaining fans (and therefore potential revenue) as a result. In the second, the artist is getting no credit for having created the material. This comparison roughly applies to software copyrights, though attributing the use of libraries with software typically requires the company's legal team and often adding stuff to documentation that no one wants there. I've had to avoid the use of some very popular free software before simply because legal refused to put the required blurb where it needed to be.
Read this article:
p eak_at_intels_65nm_pentium_4-11.html#power_consump tion
http://www.tomshardware.com/cpu/20051007/a_sneak_
In short, decreasing the die size has allowed Intel to reduce power consumption a bit, but it's also increased thermal density to such a degree that they can't clock them as fast as even the current crop of 90nm processors. Why upgrade to these chips?
The article also says "Bart continues to bate his teachers." While 'bate' is a real word, I don't think it was intended in this case. Proofreading FTW!
if he behaves this way in public? I sincerely hope he doesn't have children.
in 212 BC, Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire.
If the enemy ships were anchored within bow and arrow range, I suspect that while Archimedes was fiddling with his mirrors, a few archers dipped their arrows in pitch and fired them at the fleet. Eventually, when Archimedes finished aiming his master weapon he was overjoyed to discover the fleet in flames. Archimedes reported his success to the king, and went down in history as the oldest recorded example of a horribly over-engineered solution to a simple problem.
as tin foil hadn't been invented yet, his enemies would have had no viable defense against this weapon. Devastating!
Charge 10 times more for it than it's worth and force them to buy a new copy once a year ;-)
that inspired my comment. The usability of both of these products is quite poor. It just happens that I find Blackboard slightly less annoying to use than WebCT.
WebCT is worse. At the very least, I hope this merger will eliminate WebCT from the field.
I hear Peter Jackson found a whole town of them there.
For what it's worth, the criteria for this law are very similar to the FCC's profanity rules (through 1995 or so at any rate). The real problem in both cases is that everything is subjective and there is no formal review process in place to question uneducated rulings. Assuming games could be considered "art" or that a game may include content which is intended to provoke discussion, the possibility of hasty judgements resulting in 'improper' censorship are very real (assuming a store may not carry a game because it has an 'M' rating, which seems a reasonable assumption). For reference, this has happened with radio broadcasts from time to time (google "Sarah Jones" and "Your Revolution"), and the resulting mess took years to sort out--a time which could make or break a game company .
What exactly does this law hope to accomplish? Alcohol and cigarette laws make sense to a degree--a child can drink or smoke anywhere and both involve health risks. But games are typically played at home (where parents should be aware of the child's activities), and there are obviously no health risks involved. I half wonder if the movie industry lobbied for this law in order to regain viewership lost to video gaming.
I'm not sure I understand the logic behind your argument. Why is it necessary to eliminate technology simply because you don't know how to manage your free time in its presence? No one ever said that you have to answer the phone just because it's ringing. You can even turn the ringer off. How did this ever get to +5, insightful?
And the bulk of it is for bathing and the like. Amazing. I can understand this for established camps perhaps, but surely they don't bother with this on the front lines? If cleanliness is really that much of an issue, wipe down with a sponge. It'll take half a gallon of water and you'll end up almost as april fresh.
A soldier in the desert needs about 20 gallons of water a day, for all purposes
Unless "all purposes" includes taking a shower or using a flushing toilet I'm not sure I understand this estimate. A person in the desert needs to drink perhaps 1 gallon of water a day to stay sufficiently hydrated. Where does the other 19 gallons go?
and because of IP issues. The industry is resisting standardization to some degree because companies want to make money selling library code and the like. Personally, I relate software engineering today to pre-industrial tradework like blacksmithing. Most code for every project is written from the ground up and technical tricks are jealously guarded by many software houses (IP and non-compete laws now vs. less formal methods way back when). Eventually, however, the glory days will end as the average project size simply gets too large to be managed in such a manner. Particularly when software integrity becomes more of an issue. What will happen if the law changes such that all software must provide some stability and safety guarantees? As it is, things are abysmal. I've had to replace my last two cellphones (Motorola... never buying one again) because the firmware was garbage and they crashed and freaked out constantly. And cellphones are products that are expected to Just Work. What does that say about the rest of the industry? Calling the process an art is just a cop-out as far as I'm concerned. There's a difference between striving to build a flawless product and in embracing the flaws as a consequence of the artistic process--the latter group is just excusing their lack of skill or discipline.
Anyone? Or am I the only person that thinks that web browsers stink as a platform?