How does VirtualBox CALCULATE how many virtual CPUs are available? - cpu

I've tried to get an answer to this question in VB IRC channel, I've looked around stackexchange, stackoverflow, superuser, and elsewhere. Answers come close, but not what I am wanting to know.
This is a curiosity question only, not one of necessity. I just want to know how things work. It has nothing to do with any bug, enhancement request, or security issue. If you feel this forum is not the place to get an answer to this, please refer me to the proper venue. Thanks. (Although it is hard for anyone to imagine that VBox's own forum could be the wrong place, I did not see an answer to my specific question or a place to post to an appropriate category.) Whatever happens, please don't close my question without at least pointing to a better resource (I hate when that happens!). Thanks again.
Now, the question: How does virtualbox's host driver calculate the total number of virtual CPU's to provide?
(Please note I will not respond to answers from people who did not really read the question, or at least first ask for more clarification. I think this is a VERY straight-forward question.)
Let me break the question down so as to be as precise and concise as possible as to what I am really asking. I am curious to know how the VirtualBox HOST software (whatever portion that may be) determines how many VIRTUAL CPUs appear on the configuration interface where the user selects how many VCPUs they would like to apply to a specfiic VM.
What I am NOT asking: I am NOT asking about the miracle of virtualization hardware, etc., in general; I understand multiple cores and multiple threading, VTx, etc. I am NOT asking how many I should use for a specfic VM or application. I am NOT asking for help in configuring any specific VM in my question. I am NOT asking anyone to ask ME why I need to know -- I told you already; I am merely curious. If my specific question does not interest you, that's fine. Again, this is just a simple, straight-forward question: How does VBox arrive at the number?
What I already know: It is true that, at least generally, the answer is 2x as many as physical CPUs; OK, if so, why 2x and not 3x or some other multiplier? (I know fractional amounts won't work for odd-number of cores or threads; I am just being as general as I can be.) For instance, on my Phenom II X6, VirtualBox presents me with up to 12 VCPUs. If the answer is the threads, well, that can't be since my particular Thuban does not have threads (some Thubans do, some don't). What my Thuban DOES have, though, is hypertransport, but not hyperthreading. Likewise, my old Phenom II X2 will allow 4 VCPU's in Virtualbox.
I have already read the numerous responses on the sites mentioned above admonishing users NOT to use more than one VCPU per VM because it adds overhead (for one thing, you must run the IOAPIC, which introduces a performance hit). I've also read posts where the question sounds like mine, but they do not ultimately give an answer to this.
Is the answer some kind of sigma sum or logarithmic formula? Is it complex enough to exceed this forum's formatting capabilities? Hard to imagine why it is so difficult to get an answer to this, which I figure would have been asked and answered many times over. I really want to know why it seems to be 2x usually; why that is the "magic" number. If I read the source code (assuming this is available), will the comments explain why?
I will really appreciate and admire the soul(s) who read and answer this question, and not some other question not being asked. I also hope you will not redirect me to the dark and hostile channels of IRC; there are some very sociopathic entities on IRC whose remarks remind me of some of the unsubs on Criminal Minds. Note that I said "some" -- there are helpful people there also. Not meaning to antagonize; I just hate going to IRC anymore. If you know of a specfic helpful nick on IRC with this, I'd appreciate that also.
BTW, I have been googling for answers to this and other questions and reading SO, SE, and SU boards and I see where some people respond with answers that are totally irrelevant. That's the reason for what may sound like a harsh tone by me. This is my first post, and I hope the response will be more positive than a few of my experiences on IRC.

It seems you are asking "How does the VirtualBox GUI calculate the available range for the Processor(s) slider under the System settings?"
Because VirtualBox is open source (and very clean, well written source) it isn't too hard to dig into the code and research out the answer. Digging down into the /src/VBox/Frontends/VirtualBox/src/settings/machine folder you can see all the UI* files that comprise the settings UI elements. The specific file that will have your answer is UIMachineSettingsSystem.cpp. Starting on about line 45 (as of revision 43459), you can see the following code:
/* Setup constants */
CSystemProperties properties = vboxGlobal().virtualBox().GetSystemProperties();
uint hostCPUs = vboxGlobal().host().GetProcessorCount();
mMinGuestCPU = properties.GetMinGuestCPUCount();
mMaxGuestCPU = RT_MIN (2 * hostCPUs, properties.GetMaxGuestCPUCount());
The mMinGuestCPU variable and associated GetMinGuestCPUCount() method (and mMaxGuestCPU / GetMaxGuestCPUCount()) should be relatively straightforward - typically it will be 1 for the min and the max will be the number of physical/logical cores available on the host.
Thus, to answer your question - the scale for the slider is typically 1 through two times the number of cores available. I would strongly encourage you to download the source code and dig into the methods that calculate those numbers and see for yourself how they are calculated and the nuances that are involved. Specifically the vboxGlobal().host().GetProcessorCount() method.

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How does a programmer think? [closed]

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This may be a hopelessly vague question. But I am interested to hear whatever logical thought processes people go through when learning a new concept or trying to get their brain around code they might not have ever seen before.
Basically, what general steps does one take to to break down problems and what does it take to "get it"? If you were to diagram a flowchart of how your mental process works when you look at code or try to solve a problem what might it look like?
What common references, tips, and mental assumptions do you find useful in problem solving?
How is this different between different domains? For example in what ways is a web programmer's thought process similar or different from a traditional desktop app developer's process?
I'm a big believer that no matter what type of application you're looking at for the first time, may it be a web app, a desktop app, a device driver, or whatever else, there are three steps one developer usually follows in order to understand how it works:
Get the big picture :
What kind of app is this (web, desktop, ...)?
How is it layered (standalone, client-server, n-tier, ...)?
What is the app's purpose? What is it supposed to do?
Who is the app made for?
See how it works :
What language(s) is (are) used?
How is the code structured?
How is the data structured?
Understand (or at least try to) the way the app has been thought through:
Has it been thought through at all?
Is the app clearly optimized? (For performances? For readability?)
Is the app finished? Or is there room for evolutions?
Are there signs of multiple releases?
etc...
The 1st and 2nd steps are purely technical, while the 3rd MUST be as untechnical as possible... it's more about psychology and understanding how the app has been built. It obviously requires experience, but as long as you think hard enough and don't waste your brain's time with technical details, you'll eventually get it.
This whole process shouldn't require the use of a keyboard. You're only supposed to read, think, and take notes on a paper (I'm not kidding: pen and paper!).
Ho ho, good luck with this one. It's a great question and I'm sure you'll get a ton of answers. Although I have to say I cannot give a satisfactory answer to this - the last thing I would describe my thought processes as is a flow chart - I don't think there is any golden formula for this.
The only tip in problem solving I can recommend is discussing it with somebody else. In those times when you hit a brick wall, going through it with a colleague is invaluable. Quite often, as well, they will actually not even add much to the discussion - in the process of getting all your thoughts out in the open, the solution can become clear.
People are notoriously bad at examining their own thought processes, but I'll give it a whirl. I test very high for visuo-spacial ability in IQ tests, medium-to-high for verbal skills, and moderate for mathematical skills (explains my A-level Maths grade, I suppose). amd when I start to design software, I think in terms of shapes and the connections between them. When it comes to describing these thoughts to others (or clarifying them for myself), I use simple block diagrams or the object diagrams taken from Jacobson's Objectory method - NOT the over complex stuff that UML suggests. I sometimes write textual descriptions of complex things, mostly as reminders to myself, but never use numbers or maths.
Of course this is just me - I've worked with maths whizzes who were just as good or even better programmers than myself.
I don't think... I process.
This is actually less flip than it sounds. I always break down tasks into their components and then break these down further, and that doesn't just go for writing software! Much like #Mark Pim U go through things sequentially.
My wife gets really annoyed when I make dinner because I take so long to get started.
Divide & Conquer
I start by trying grasp the entire problem as it is, and then start to find patterns I can recognize, and do the same for them in a kind of recursive process, until I have a broken down solution I can implement and follow more easily.
This is one of the rare times I would answer with "it just works." I learn things by steamrolling through them. I don't have gimmicks, or devices to help me. Took me some time to learn PHP, but after that Javascript was much easier. Once you tackle one thing, the next items become cumulatively-easier.
Personally, I conduct an internal dialogue with myself 'OK so we need to loop over this list of integers.' 'But we can break when we find the value we want.' 'OK, will the list definitely be initialised when we start?'
I'd be interested to see if any psychological research had been done on problem solving techniques.
Similar to Jonathan Sampson - it kind of just works.
When I'm attacking a real problem, I try and think of the most logical way of getting through it is.
Then, when everything goes wrong (as it usually does), I have to make hundreds of sidesteps to get things done. Just keep focusing on that end goal, that logical way and you'll get there.
Eventually though, it decides to work for me and I end up with a finished product that is usually nothing like I planned it out to be. As long as the customers are happy, I am!
Personally, I see code in my head pictorally rather than textually (like Neil Butterworth) - it's a bit hard to describe since (quoting STIV) "there's no common frame of reference."
My main skill is identifying similarities between models or systems I already know about and the task at hand. The connections between some of these can seem quite abstract; the key is to spot the connections. This leads to the abstraction of common patterns and approaches which are widely applicable. Related to this, the most important thing I learnt about algorithms was that the problem is never 'come up with a smart algorithm to solve X'. It's 'model problem X such that it can be solved by existing smart algorithm Y'.

Techniques to follow when you are stuck programming [closed]

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When I am stuck with a problem:
I search Google for code snippets.
I look at isolating the problem, so that I can better explain it to others in order to get answers.
What search techniques do you use to find the solution to your problem?
I started asking questions in Stack Overflow.
What other techniques or methods do you follow, to fix the problem more quickly?
Go and do something else. No, really. I've found that putting the problem away in the back of my mind helps. I can't count the number of times I thought of a great solution to something I've been working on when I was working on something else, or watching TV, or eating. It seems your brain is still working on the problem in the background.
If that fails to solve your problem, try talking to someone. You'd be surprised how often others can give solutions to your problem that are so simple you'd facepalm.
Well there's:
Google
Google
Google
Stack Overflow
Google
Google
Maybe a book if I have one.
Seriously, I started (hobby) programming in the 1980s and even into the mid 90s you had to know things and have a technical library. Then Google came along and it's easier to Google something than it is to look up (bookmarked!) API documentation (Google "java stringbuilder" will get me there faster than navigating will) let alone an actual book (electronic or paper).
Most problems you're trying to solve have been solved before. Many times.
The rest of debugging comes down to decomposition, possibly unit testing (which is related to decomposition) and verifying your assumptions.
By "decomposition", I mean that your solution is structured in such a way that small pieces can be individually tested and readily understood. If you have a 7000 line method you're (probably) doing something wrong.
Understanding what assumptions you've made is key too so you can verify them. For example, when I started with PHP I wrote a piece of code like this:
$fields = $_SESSION["fields"]; // $fields is an associative array
$fields["blah"] = "foo";
and I was scratching my head trying to figure out why it didn't work (the array wasn't being updated next time I queried $_SESSION). I came from a Java background where you might do this:
Map fields = (Map)httpSession.get("fields");
fields.put("blah", "foo");
and that would most definitely work. PHP however copies the array. A working solution is to use references:
$fields =& $_SESSION["fields"]; // $fields is an associative array
$fields["blah"] = "foo";
or simply:
$_SESSION["fields"]["blah"] = "foo";
The last thing I'll say about debugging and writing robust code in general is to understand the boundaries of your solution. By this I mean if you're implementing a linked list then the boundary conditions will revolve around when the list is empty.
Explain the problem to a colleague, or write it down to describe it. That will makes you think a different way, from a different perspective. In order to be more accurate, and to describe the context of the problem, you'll step back, get a higher level view of the problem, you may find out think you overlooked something that is actually important.
Sometimes, you even find the explanation before ending your description.
My best friend for many years has been to jump on my bike and go home. Just getting away from the keyboard has solved many problems over the years for me.
If the problem lasts to the end of the day, I try and consciously lock the problem away for solving before I go to sleep.
I realise this sounds a bit out there, but it has been very common in my experience that I'll wake up with at least an alternate approach to the problem, if not the full-on solution. The idea is not to stress about it - but actively decide to solve it over night. That way you can go to sleep without worry.
I think eating well, regular exercise and good sleep are huge contributors to the problem-solving process.
Usually I'll try nut out the problem for a few hours or so, trying different things writing it on paper, making diagrams. If none of that works I'll usually work through the following options.
Put a sticky note on my monitor and keep going with something else
Glance at the note through out the next few hours to keep the problem in the back of my mind
Google for similar problems and the methods used
Consult a co-worker or a friend
Ask on a forum such as stackoverflow
Give up and design the problem away or design a way around the problem so it can be dealt with some other time and stick a TODO note at the site of said workaround
Don't forget Google Code Search
It's often best to clear your head by doing something other than programming for a little while. See this answer for an example - I did it while struggling with a particularly thorny bug, and when I came back to the problem I solved it in about a minute.
Usually I try to solve it until I go to sleep.. Sometimes I write on paper what the code is doing and then I divide it in pieces; I try to know how the variables of the program change when it's running.
Try solving a much smaller version of the problem first and see how you get on with that.
Once you've done that the bigger problem won't look so scary.
Ask yourself: is solving this particular tricky problem really important to what you doing?
For the purposes of your application (or whatever the big picture is) is there a similar but easier problem that you could address to accomplish broadly the same thing.
Normally, I would get pen and paper and try to work out the details of the problem there. If that doesn't help, Google. Failing that, I'd do something else for a while, or ask online. Worked for me so far.
The fact you are stuck might be a 'code-smell'. Suggesting that their is something wrong with the design or approach somewhere else. Try to put your finger on what's causing this and fix this instead.
When you come back to your problem it might no longer exist.
One more time, browse thru what I think might be relevant, then take nap.
There are two other answers which mention sleeping or napping, but this deserves more emphasis. It is now known that there's SERIOUS machinery in there which goes to work when you sleep. Google (( CBS SCIENCE SLEEP )) will get you to a great free video.
If I can't figure out how to solve the real problem, I try to consider a simplified version of the problem. To take a simple example: I recently had the problem of finding a set of shipping routes to get an item from point A to point B, when there is not necessarily a direct route from A to B, but there might be an A to C and then C to B, or A to C, C to D, and then D to B. (I'm sure the airlines and railroads do this all the time.) That was fairly complex, so I tried looking first at the simple case: a direct A to B. That was easy. Then consider how I'd handle it with one stop along the way. Then consider two stops. At that point I was able to see the pattern to a solution.
Solutions to a simplified version of the problem may end up being a part of the bigger solution, with some additional complexity wrapped around them. But even if not, the exercise of solving the easier problem often gives you ideas on how to solve the real problem.
The main techniques I use (should be followed in order so that you can reuse what you have done in previous steps to be more efficient):
Define your issue: Try to clearly define what's the problem, and what's expected. See 2 to help you.
Collect data about the bug: Log everything: your attempts, the expected result, the observed result. This will avoid the need to redo several times the same tests (because your mind cannot memorize it all), and probably help you see the bigger picture.
Reduce your problem. This is true in general for any abstract modelling of natural phenomenons, but it's even more true of programming, because programs are very complex entities. You should try to reduce your code to a minimal program that reproduces your issue. Automated tools exist.
Talk to someone: several anecdotes affirm than about 2/3 of the bugs are resolved just by talking about it. See the Helpful Teddy Bear anecdote. If you have previously reduced your program to a minimal program, and have a clear definition of your issue, both will be useful to your explanation.
Reach for collaborative help: search on Google and on StackOverflow, and post if you can't find anything that answers your problem (but first see 1, you must have a clear definition of your problem).
As you can see, I put the collaborative help as the last step, because you should only ask for help after you have clearly defined your issue and tried to reduce the problem and fix it by yourself. If you reach for collaborative help before having tried the previous steps, you will either end up with a poor help or figure it out by yourself as soon as you have posted.
Also you can be interested in the Coursera Software Debugging course, which also describes several automated debugging methods.
Go to the toilet.
You move, so your brain gets oxygen.
You relax, so you focus on other things.
Peeing for innovation! :)

Number of lines of code in a lifetime [closed]

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One of the companies required from its prospective employee to give the number of lines of code written in the life time in a certain programming language like Java, or C#. Since, most of us have a number of years of experience in different projects in multiple languages and we hardly keep record of this, what would be the best approach to calculate this metrics. I am sure the smart members of stackoverlow.com will have some ideas.
This is a very respected company in its domain and I am sure they have some very good reason to ask this question. But what makes it also difficult to answer is the type of code to consider. Should I only include the difficult algorithm that I implemented or any code I wrote for e.g. a POJO that had 300 properties and whose getters/setters were generated using IDEs!
The best response to such a question is one of the following:
Why do you want to know?
What meaning would you attribute to such a number?
Is it OK if I just up and leave just about now?
I would seriously question the motives behind anyone asking such a question either of current or prospective employees. It is most likely the same type of company that would start doing code reviews focusing on the number of lines of code you type.
Now, if they argue that the number of lines of code is a measure of the experience of a programmer, then I would definitely leave the interview at that point.
Simple solutions can be found for complex problems, and are typically better than just throw enough lines of code at the problem and it'll sort itself out. Since the number of bugs produced scales linearly and above with the number of statements, I would say that the inverse is probably better, combined with the number of problems they've tackled.
As a test-response, I would ask this:
If in a program I am able to solve problem A, B and C in 1000 lines of code, and another programmer solves the same problems in 500 lines of code, which of us is the best (and the answer would be: not enough information to judge)
Now, if you still want to estimate the number of lines, I would simply start thinking about the projects the person has written, and compare their size with a known quantity. For instance, I have a class library that currently ranges about 130K lines of code, and I've written similar things in Delphi and other languages, plus some sizable application projects, so I would estimate that I have a good 10 million lines of code on my own at least. Is the number meaningful? Not in the slightest.
Sounds like this is D E Shaw's questionnaire?
This seems like one of those questions like 'How many ping-pong balls could you fit in a Boeing 747?' In that case, the questioner wants to see you demonstrate your problem solving skills more than know how many lines of code you've actually written. I would be careful not to respond with any criticism of the question, and instead honestly try to solve the problem ; )
Take a look at ohloh. The site shows metrics from open source projects.
The site estimates that 107,187 lines of code corresponds to an effort of 27 Person Years (4000 lines of code per year).
An example of the silliness of such a metric is that the number is from a project I've been toying with outside work during 2 years.
There are basically three ways of dealing with ridiculous requests for meaningless metrics.
Refuse to answer, challenging the questioner for their reasons and explaining why those reasons are silly.
Spending time gathering all the information you can, and calculating the answer to the best of your ability.
Making up a plausible answer, and moving on with as little emotional involvement possible in the stupidity as possible.
The first answers I see seem to be taking the first line. Think about whether you still want the job despite the stupidity of their demands. If the answer is still Yes, avoid number 1.
The second method would involve looking at your old code repositories from old projects.
In this case, I would go with the third way.
Multiply the number of years you have worked on a language by 200 work days per year, by 20 lines of code a day, and use that.
If you are claiming more than one language per year, apportion it out between them.
If you have been working more on analysis, design or management, drop the figure by three quarters.
If you have been working in a high-ceremony environment (defence, medicine), drop the figure by an order of magnitude.
If you have been working on an environment with particularly low ceremony, increase it by an order of magnitude.
Then put the stupidity behind you and get on with your life as quickly as possible
Depending on what they do with the answer, I don't think this is a bad question. For example, if a candidate puts JavaScript on their resume, I want to know how much JavaScript have they actually written. I may ask, for example, for the number of lines in the largest JavaScript project they've written. But I'm only looking for a sense of scale, not an actual number. Is it 10, 100, 1000, or 10,000 lines?
When I ask, I'll make very clear that I'm just looking for a crude number to gauge the size of the project. I hope the employer in the questioner's case is after the same.
It is an interesting metric to ask for considering you could write many many lines of bad code instead of writing just a few smart ones.
I can only assume they are considering more lines to be better than fewer. Would it be better to not plan at all and just start writing code, That would be a great way to write more lines of code, since at least if I do that I usually end up writing everything at least twice.
Smart of stack overflowers would generally avoid organization that ask this kind of question. Unless the correct answer is "huh, wtf??"
If you were to be truly honest then you'd say that you don't know because you have never viewed it as a valid metric. If the interviewer is a reasonable/rational person, then this is the answer they are looking for.
The only other option to saying you don't know is to guess, and that really isn't demonstrating problem solving skills.
Why bother calculating this metric without a good reason? And some random company asking for the metric really isn't a good reason.
If the company's question is actually serious, and you think the interview might lead to something interesting, then I would just pick a random number in order to see where that leads :-)
Ha, reminds me when I took over a C based testing framework, which started out as 20K+
lines that I ended up collapsing into 1K LOC by factoring down to a subroutine instead
of the 20K lines of diarrea code originally written by the original author. Unfortunately,
I got spanked harder for any errors in the code as my KLOC's written actually went
negative... I would think long and hard about shrinking the code base in a metrics driven organization....
Even if I agree with the majority in saying that this is not a really good metric, if it's a serious compmany, as you say, they may have their reasons to ask this.. This is what I would probably do:
Take one of your existing project, get the number of lines and divide it by the time it took you to code it. This will give you a kind of lines per hour metric. Then, try to estimate how many time you have worked with that specific language and multiply it with your already calculated metric. I honestly don't think it's a great way.. but honest, this isn't a great question neither.. I would also tell the company the strategy I used to come up with this number.. maybe, MAYBE, this is what they want.. to know your opinion about this question and how you would answered it? :p
Or, they just want to know if you have some experiences.. so, guess an impressive number and write it down :D
"This is a very respected company in its domain and I am sure they have some very good reason to ask this question"
And I am very sure they don't, because "being respected" does not mean "they do everything right", because this is certainly not right, or if it is, then it's at least dumb in my opinion.
What does count as "Lines of Code"? I estimate that I have written around 250.000 Lines of C# Code, possibly a lot more. The Problem? 95% was throwaway code, and not all was for learning. I still find myself writing a small 3-line program for the tenth time simply because it's easier to write those three lines again (and change a parameter) than go search for the existing ones.
Also, the lines of code means nothing. So I have two guys, one has written 20% more Lines that the other one, but those 20% more were unnecessary complicated lines, "loop-unrolling" and otherwise useless stuff that could have been refactored out.
So sorry, respected company or not: Asking for Lines of Code is a sure sign that they have no clue about measuring the efficiency of their programmers, which means they have to rely on stone-age techniques like measuring the LoC that are about as accurate as calendars in stone-age. Which means it's possibly a good place to work in if you like to slack off and inflate your Numbers every once in a while.
Okay, that was more a rant than an answer, but I really see absolutely no good reason for this number whatsoever.
And nobody has yet cited the Bill Atkinson -2000 lines story...
In my Friday afternoon (well, about one Friday per month) self-development exercises at work over the past year, tests, prototypes and infrastructure included, I've probably written about 5 kloc. However one project took an existing 25kloc C/C++ application and reimplemented it as 1100 lines of Erlang, and another took 15kloc of an existing C library and turned it into 1kloc of C++, so the net is severely negative. And the only reason I have those numbers was that I was looking to see how negative.
I know this is an old post, but this might be useful to someone anyway...
I recently moved on from a company I worked at for roughly 9.5 years as a Java developer. All our code was in CVS, then SVN, with Atlassian Fisheye providing a view into it.
When I left, Fisheye was reporting my personal, total LOC as +- 250,000. Here's the Fisheye description of its LOC metric, including the discussion on how each SVN user's personal LOC is calculated. Note the issues with branching and merging in SVN, and that LOC should usually only be based on TRUNK.

How do you start Knowledge Transfer? [closed]

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Do you use a formal event to get people talking in your IT department? Like a monthly meetup in a social place, a internal wiki/chat space or just a regular "information market" with some presentations about technology or projects made by your staff for your staff? Do you invite Sales people to participate or is it a closed event for programmers only?
How do you get people to participate in these events? Do you allow them to spent work time on knowledge transfer? Or do you understand it as an integral part of the work time?
I wonder how to monitor the progress of knowledge transfer itself. How do you spot critical one-person spots of failure in your projects? There are several methods to avoid it, like staff swapping or the "fifo" attempt on bug fixing.
Note: Ok, this is a very very noisy question and I hope to fix it after a few comments. Sorry for the mixup.
edit: My personal experience is that there is a very high barrier for people to start contributing. It looks like they won't put in the (minimal) extra time to edit our wiki, or spend the hour in the afternoon to talk about technology topics with the developing staff. It's like people don't like our wiki, our document management system or the meeting. Maybe it's because it's all free-to-use and not forced by the management. But I don't like to force people into it - but is it the right way?
One example: Our wiki holds pages about projects, telling who worked on it to get a first contact in case of questions. But nobody besides a colleague and me is creating this pages...
Knowledge Transfer and Knowledge Management have one drawback. They seem to cost an aweful lot: if everybody knows what I know, am I still needed? All the time I use to bring others up to speed, what do I gain from it?
The best way to go about this is to be an example. Share your knowledge; in a wiki, blog about it, talk about it, make it easily accessible, and talk about the benefits you have from that: less people come to interupt and ask you stuff, as they can get an answer easily without even getting up. And show them that you are still there.
This with all the other things mentioned will actually win out. One more thing: one of my employers kept on paying me 1/3 of my salary for another year after I left (on my own initiative), just to keep my knowledge-base up and running. Did he have to? No, it was his property anyway. But it motivated people still working for him to share their knowledge.
I think all of the above. But you're forgetting the most important way.
The most efficient way to transfer knowledge is to have people work together. You might think about doing 1 on 1 code reviews or even pair programming and make knowledge transfer an intergral part of the work.
I think it depends on the knowledge you are trying to transfer. I've found the following:
Technical Knowledge: "How to guide" with screenshots and a short demo - similar to the way you will see new features at a conference. The added benefit of this is what you have got is documented for when you leave the company.
Problem solving: informal discussions, short internal projects, lessons learned and an internal FAQ system which EVERYONE is responsible for updating.
Soft Skills (people skills): social meetings/outings/informal events etc.
Measuring that is going to be difficult though, as no matter how you transfer your knowledge there will always be varying degrees of uptake, after all, just because I do something one way doesnt mean its correct. Another developer/designer/manager may have a different way of doing the same thing with the same end result.
Mauro
At my workplace we use a wiki. The workplace is small enough (~20 people) so that you can always ask the person who was most involved in a particular project, however it is expected that you have searched on the wiki before you ask "the expert". If you cannot find your answer in the wiki, then you should add it after you have discussed it with your co-worker.
One word: Lunch
You should encourage people about things that you want them to do. You should "feed the animal". Look at stackoverflow; what do you think about badges? Why do you think this wonderful things exist? Thanks to ego, there is nothing you can't get it done. Give them badges, real badges, wearable badges. They will wear with happiness, they will do with happiness.
Btw, yes, I am a boss :)
Although i am still a student, when i did work experience 12 months ago, the all IT departments from within the corporation (I was 'working' for large corporation which own several mines in the area) would have a daily telephone conference, where each employee would say what they had been doing etc, and then talk about something new they had discovered and any other interesting tid-bits.
Couple ways I have seen so far:
Wiki is suitable for internal knowledge, for example environment, project specific topics.
Open doors policy
Encourage asking questions.
Voluntary presentations. Find out who have special knowledge and make it easy and attractive to set up a short presentation about it.
Project post mortem documents. A wrap up meeting moderated by someone outside project team held after project is finished or terminated.
Compulsory presentations.
Project presentation when they go live. Technologies used etc.
In case someone is sent to conference, he should have a presentation about new technology he saw.

A good pattern/solution to the social web user issue of point whoring? [closed]

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Closed 11 years ago.
Take any social website like Digg or Stack Overflow that somehow lets users reward points for stories, questions, etc..
What happens is quite similar to the process that lead to the rise of tabloid newspapers that feed only headlines and no content to its readers.
Users are usually smart enough to figure out strategies to maximize their point rewards regardless of whether that strategy harmonized with the goal of the website or not.
I identify the following problems
People will swamp more general and more entertaining questions with answers. Answering more specific questions requires actual domain knowledge.
Getting most points is often tied to involving most users. Given a random web crowd this unfortunately means mostly generic, subjective, argumentative and unspecific entries.
As the creator of a social website you have the unique chance to influence social behavior towards a favorable direction. I think that the influence the system has on the behavior of the people far outweighs the initial seed of users.
I'm interested in patterns/solutions that aim to solve this problem in terms of:
ranking algorithms
expert systems
limiting/creating ways of social interaction
information that is provided/hidden
In particular, given the perspective of Stack Overflow, how could one solve entries like "What's your favorite programmer cartoon" become the most popular entries (I pick this one because it is a good example for the undesired phenomenon).
The most important lesson with regard to the design of any social computing is that community dynamics problems cannot be solved purely by technological means.
In other words, whatever the solution you implement, if you have users to whom getting points (or trolling or getting involved in flame wars or whatever other disruption) is more important that participating in the community, that is what they will do.
When designing the solution, you "simply" have to make sure that there are sufficient benefits (badges, entertainment, information, rewarding feedback) in place for people who aren't in it just for the points. Then, if you are very lucky, you will attract the right kind of people.
This may seem trite, but it is one of the most importat results of CSCW research (Olson and Olson, 2000): unless users are prepared to collaborate/play fair/be productive, then no amount of technology is going to solve that problem.
This isn't fundamentally different from asking what's the best way to stop people from cash whoring in real life. Looking at it in that context, I suspect the only way to stop this behaviour is to remove the opportunity ie don't use points (or money).
The problem is that if you do that, there's no quantifiable reason to get out of bed.
Points and cash both measure social status and ability to influence others. Ability to sequestre resources is a primary sexual selection criterion, which is why greed is so powerful; it is a direct sublimation of the sex drive.
I find the voting system that Stack Overflow uses to be quite good. Other people essentially judge you as an expert or not. And the good answers bubble up to the top.
I'd stray away from punishing people who don't get voted for, and maybe have some threshold for those who get consistently voted down, losing points.
That said, with popular topics most people won't be bothered sorting through the flack to find the diamonds in the rough. So you are going to lose some good answers.
Also Stack Overflow seems to punish people who post lost of unvoted answers... My score went down after posting this as I have a few posts with 0 votes.
[Update]
In response to comments:
I think if you want more specific answers you have to dig deeper and look at a questions for a particular tag. I think the recent post What's your favorite “programmer” cartoon? has shown that people will swamp more general and more "entertaining" questions with answers as they are more like procrastination. Answering more specific questions requires actual domain knowledge.
As for why my score went down it may have been a bug. My score went from 91 to 81 when I posted this answer and then rose to 111 after that. As I'm not privy to the algorithm that Stack overflow uses, I assumed that that was what had happened.
It might just have normalised my score.
[Update 2]
I think that social networks have to police themselves. They are owned and run by the community by their very nature. Just looking at the AACS Revolt that happened on Digg last year is proof enough that you can't control it.
The trick is to have enough users who will mod down the garbage and mod up the good stuff.
Perhaps hiring a number of moderators who can do this full time, or even just giving a few people who have proven themselves to be good citizens moderator rights, with extra weight on their moderation, most people online live for this kind of recognition and some might be willing to do it for free as they will have become members of some kind of social networking elite.
The question is how do you stop them from abusing this power? As Stan Lee is fond of saying: With great power comes great responsibility.
It's probably hard to have a completely workable solution. Essentially, if the reason people attain points has a positive effect on the community, then point-whoring will increase the quality of the community over time.
Would a measure that decreases the rate at which points grow in proportion to the number of points attained be workable?
(i.e first 100 points are 'normal', next 100 take 20% longer to attain, etc)
Where there's a lot of people you should always expect the casual jerk or childish individual or attention whore or troll to show up. I don't think there's a method, a scientifically proved strategy, a technology to prevent this from happening. After all programmers are (almost always= people, also, and people tend to be quite diverse in behavior, communication skills, patience to bear the stupid, self-consciousness, sense of opportunity and even common sense. Being an heterogeneous group is something that might probably enrich everyone involved.
There shall be, nonetheless, a system to slow down the annoying people. Downvoting and closing question and answers might work - provided that the vast majority of the participants are well-behaved, responsible adults. If this is not the case... well, then everyone who feels offended would better bail out, because there's no value in attending a community where these tenets are widely disregarded.
The chance is that if the subject around which the community gathered in the beginning is quite selective in itself then a natural selection will occurr in the long term. I mean: if someone is REALLY interested in programming after a while he/she will calm down, ask more intelligent answers, give more ponderate answer, more polite comments...
This is fundamentally the same as making a startup.
The initial moderators, hired by the owner/ceo/founder(s), set the tone for the whole community.
Fortunately Jeff and Co. are moderating as well, so we can look at their example as we choose what stories to dismiss.
I find this to be a very difficult problem, though, as I too enjoy these offtopic conversations, and I know there will be backlash against me, individually, if I close some of these topics - I've already experienced it, and other moderators have to some greater degree.
But these are growing pains in any community, and there's no technical solution. Jeff et al need to cultivate the culture here so that the memes and DNA of the community are set and directed in a good direction.
But it's not as easy as that either, because until you start a community you don't know what it's capable of, or what it will become. You have to let it grow a bit itself, and exercise light authority so you don't stifle something that may be better (inevitably will be, actually) than your initial vision.
In other words, the key here is to solve the social problem with a social solution - select strong moderators that will set the tone and enforce it.
There is no way, technically, to prevent people from gaming the system, especially when there are other humans in the feedback loop - they will always find a way to game the other players into doing what they want.
-Adam
It is impossible to avoid entries that are in conflict with a specific social websites goal because one cannot prevent entertainment and procrastination. But given any entry it should be easy to decide weather it is harmonizing with the websites goal.
The solution could be to reward posters if they self police/tag their entry to the right category, and give all users a way to filter out categories they do not want to see.
For instance, on Stack Overflow most entertainment posts appear because people want to collect points (hypothesis). If this assumption is correct, then the solution of the pattern above would be that whoever tags his entry as entertaining gets twice as many points for upvotes. However nobody interested in entries tagged specific is going to see it when he has entertaining filtered out.
Perhaps there could be a "difficulty" or "obscurity" multiplier for answers to less popular questions.
People will point-whore: it's in our nature to crave recognition. Trying to stop them would be a lot of work, and if you succeed, many of the largest contributors to the site might then leave.
You need to make the behaviour you desire attractive to point-whores.
The problem is that everyone wants to be included. Look at questions with 100+ answers: Who is really going to read the last one? I'm not an expert in anything, if I compare myself to others on this site, but I still want to answer questions (see I'm doing it now).
I wish someone would start a forum for some of these issues.
Perhaps you should compute reputation on something based on the ratio of votes:views. This might discourage the populism going on and focus people's attention to providing answers across a breadth of less popular but still valid and relevant questions - questions that might actually be of interest to someone.
I would actually like to do some editing and tidying up of posts - Many posts could be improved by a bit of editorial work, filling out detail or providing links to other sources. However, without a dedicated exercise in karma-whoring (on what would be off-topic posts for me) it's very unlikely I would ever my rep up to the level where I have permissions to do this in my real areas of expertise where I might actually have something of value to say.
Separate "points" into different categories. If Digg or Reddit had a "funny/lame" vote in addition to a "interesting/uninteresting" vote, one could screen out things which have a "funny" vote that's higher than its "interesting" vote.
Slashdot has a moderation system that makes such distinctions, and you can filter it such that "+1, Funny" becomes "+0, Funny". Heck, you can even make "-1, Troll" work as "+5, Troll" (not that you should, but you could).
People will swamp more general and more entertaining questions with answers. Answering more specific questions requires actual domain knowledge.
First of all, I challenge your assertion that this is a problem. More general questions will have a more general audience and will be relevant to a greater number of people. Asking a question like "How do I do OBSCURE_TASK in LANGUAGE using TOOLKIT?" is indeed more specific and probably requires more specific knowledge to answer, but is likely only to be useful to people doing that task in that language in that toolkit. Should that float to the top when it's only of interest to a small number of people? Answered obscure questions can be found by searching. Browsing is better for finding general things.
Users are usually smart enough to figure out strategies to maximize their point rewards regardless weather that strategy harmonized with the goal of the website or not.
Yes, that's the cost of involving other people in the process. They will behave based on their own desires and motivations. If you truly want to enforce a reputation system based on whether or not it "harmonizes with the goal of the website," you want a dictatorship, not a community site.

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