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  • C++ Reference Book

    - by m00st
    Can someone list a C++ book that is just a reference to the standard library? I don't need a "learning c++" book just one that is a reference. Or at least official documentation or something? Googling only reveals "fan-site" reference.

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  • Forum for Sharing OneNote

    - by jobless-spt
    I am a big fan of OneNote. Few weeks back I came across a forum where people had shared their OneNote notebooks. Now I am trying to search but unable to find that link. Does anyone know of any such/similar forum? Note: Can anyone add Tags oneNote or Microsoft-OneNote to this. Thanks.

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  • Adding sidebar to a Facebook FanPage

    - by HollerTrain
    I am viewing the Barcardi fanpage (http://www.facebook.com/home.php?#!/bacardi?v=wall&ref=ts) and I see on their wall tab they have a sidebar area they place an advert (probably html) - http://screencast.com/t/ZGE2MDhlMDM. Thoughts on how I can get this for my fan page?

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  • If I had to create a server farm what should I do? (how others companies work?)

    - by Michel
    I have a business idea but this is not really my field so I'm trying to understand what I'm really dealing with. I have a general understanding of how a web farm works, I'm a web developer and I understand the technology behind it, but I'm curious to know specifically how a web farm is set up and which professionals are involved. Things to consider probably are the hardware, the power supply, the software managment, the cooling system and if possible the usage of green technology/power recycling. Basically, can you explain me how a web hosting company is structured and how it works? A big question, I know, but from what I already read here about the subject a lot of you know this stuff. Thanks for your time guys!

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  • simple and reliable centralized logging inside Amazon VPC

    - by Nakedible
    I need to set up centralized logging for a set of servers (10-20) in an Amazon VPC. The logging should be as to not lose any log messages in case any single server goes offline - or in the case that an entire availability zone goes offline. It should also tolerate packet loss and other normal network conditions without losing or duplicating messages. It should store the messages durably, at the minimum on two different EBS volumes in two availability zones, but S3 is a good place as well. It should also be realtime so that the messages arrive within seconds of their generation to two different availability zones. I also need to sync logfiles not generated via syslog, so a syslog-only centralized logging solution would not fulfill all the needs, although I guess that limitation could be worked around. I have already reviewed a few solutions, and I will list them here: Flume to Flume to S3: I could set up two logservers as Flume hosts which would store log messages either locally or in S3, and configure all the servers with Flume to send all messages to both servers, using the end-to-end reliability options. That way the loss of a single server shouldn't cause lost messages and all messages would arrive in two availability zones in realtime. However, there would need to be some way to join the logs of the two servers, deduplicating all the messages delivered to both. This could be done by adding a unique id on the sending side to each message and then write some manual deduplication runs on the logfiles. I haven't found an easy solution to the duplication problem. Logstash to Logstash to ElasticSearch: I could install Logstash on the servers and have them deliver to a central server via AMQP, with the durability options turned on. However, for this to work I would need to use some of the clustering capable AMQP implementations, or fan out the deliver just as in the Flume case. AMQP seems to be a yet another moving part with several implementations and no real guidance on what works best this sort of setup. And I'm not entirely convinced that I could get actual end-to-end durability from logstash to elasticsearch, assuming crashing servers in between. The fan-out solutions run in to the deduplication problem again. The best solution that would seem to handle all the cases, would be Beetle, which seems to provide high availability and deduplication via a redis store. However, I haven't seen any guidance on how to set this up with Logstash and Redis is one more moving part again for something that shouldn't be terribly difficult. Logstash to ElasticSearch: I could run Logstash on all the servers, have all the filtering and processing rules in the servers themselves and just have them log directly to a removet ElasticSearch server. I think this should bring me reliable logging and I can use the ElasticSearch clustering features to share the database transparently. However, I am not sure if the setup actually survives Logstash restarts and intermittent network problems without duplicating messages in a failover case or similar. But this approach sounds pretty promising. rsync: I could just rsync all the relevant log files to two different servers. The reliability aspect should be perfect here, as the files should be identical to the source files after a sync is done. However, doing an rsync several times per second doesn't sound fun. Also, I need the logs to be untamperable after they have been sent, so the rsyncs would need to be in append-only mode. And log rotations mess things up unless I'm careful. rsyslog with RELP: I could set up rsyslog to send messages to two remote hosts via RELP and have a local queue to store the messages. There is the deduplication problem again, and RELP itself might also duplicate some messages. However, this would only handle the things that log via syslog. None of these solutions seem terribly good, and they have many unknowns still, so I am asking for more information here from people who have set up centralized reliable logging as to what are the best tools to achieve that goal.

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  • A Taxonomy of Numerical Methods v1

    - by JoshReuben
    Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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  • Scott Guthrie in Glasgow

    - by Martin Hinshelwood
    Last week Scott Guthrie was in Glasgow for his new Guathon tour, which was a roaring success. Scott did talks on the new features in Visual Studio 2010, Silverlight 4, ASP.NET MVC 2 and Windows Phone 7. Scott talked from 10am till 4pm, so this can only contain what I remember and I am sure lots of things he discussed just went in one ear and out another, however I have tried to capture at least all of my Ohh’s and Ahh’s. Visual Studio 2010 Right now you can download and install Visual Studio 2010 Candidate Release, but soon we will have the final product in our hands. With it there are some amazing improvements, and not just in the IDE. New versions of VB and C# come out of the box as well as Silverlight 4 and SharePoint 2010 integration. The new Intellisense features allow inline support for Types and Dictionaries as well as being able to type just part of a name and have the list filter accordingly. Even better, and my personal favourite is one that Scott did not mention, and that is that it is not case sensitive so I can actually find things in C# with its reasonless case sensitivity (Scott, can we please have an option to turn that off.) Another nice feature is the Routing engine that was created for ASP.NET MVC is now available for WebForms which is good news for all those that just imported the MVC DLL’s to get at it anyway. Another fantastic feature that will need some exploring is the ability to add validation rules to your entities and have them validated automatically on the front end. This removes the need to add your own validators and means that you can control an objects validation rules from a single location, the object. A simple command “GridView.EnableDynamicData(gettype(product))“ will enable this feature on controls. What was not clear was wither there would be support for this in WPF and WinForms as well. If there is, we can write our validation rules once and use everywhere. I was disappointed to here that there would be no inbuilt support for the Dynamic Language Runtime (DLR) with VS2010, but I think it will be there for .vNext. Because I have been concentrating on the Visual Studio ALM enhancements to VS2010 I found this section invaluable as I now know at least some of what I missed. Silverlight 4 I am not a big fan of Silverlight. There I said it, and I will probably get lynched for it. My big problem with Silverlight is that most of the really useful things I leaned from WPF do not work. I am only going to mention one thing and that is “x:Type”. If you are a WPF developer you will know how much power these 6 little letters provide; the ability to target templates at object types being the the most magical and useful. But, and this is a massive but, if you are developing applications that MUST run on platforms other than windows then Silverlight is your only choice (well that and Flash, but lets just not go there). And Silverlight has a huge install base as well.. 60% of all internet connected devices have Silverlight. Can Adobe say that? Even though I am not a fan of it my current project is a Silverlight one. If you start your XAML experience with Silverlight you will not be disappointed and neither will the users of the applications you build. Scott showed us a fantastic application called “Silverface” that is a Silverlight 4 Out of Browser application. I have looked for a link and can’t find one, but true to form, here is a fantastic WPF version called Fish Bowl from Microsoft. ASP.NET MVC 2 ASP.NET MVC is something I have played with but never used in anger. It is definitely the way forward, but WebForms is not dead yet. there are still circumstances when WebForms are better. If you are starting from greenfield and you are using TDD, then MVC is ultimately the only way you can go. New in version 2 are Dynamic Scaffolding helpers that let you control how data is presented in the UI from the Entities. Adding validation rules and other options that make sense there can help improve the overall ease of developing the UI. Also the Microsoft team have heard the cries of help from the larger site builders and provided “Areas” which allow a level of categorisation to your Controllers and Views. These work just like add-ins and have their own folder, but also have sub Controllers and Views. Areas are totally pluggable and can be dropped onto existing sites giving the ability to have boxed products in MVC, although what you do with all of those views is anyone's guess. They have been listening to everyone again with the new option to encapsulate UI using the Html.Action or Html.ActionRender. This uses the existing  .ascx functionality in ASP.NET to render partial views to the screen in certain areas. While this was possible before, it makes the method official thereby opening it up to the masses and making it a standard. At the end of the session Scott pulled out some IIS goodies including the IIS SEO Toolkit which can be used to verify your own site is “good” for search engine consumption. Better yet he suggested that you run it against your friends sites and shame them with how bad they are. note: make sure you have fixed yours first. Windows Phone 7 Series I had already seen the new UI for WP7 and heard about the developer story, but Scott brought that home by building a twitter application in about 20 minutes using the emulator. Scott’s only mistake was loading @plip’s tweets into the app… And guess what, it was written in Silverlight. When Windows Phone 7 launches you will be able to use about 90% of the codebase of your existing Silverlight application and use it on the phone! There are two downsides to the new WP7 architecture: No, your existing application WILL NOT work without being converted to either a Silverlight or XNA UI. NO, you will not be able to get your applications onto the phone any other way but through the Marketplace. Do I think these are problems? No, not even slightly. This phone is aimed at consumers who have probably never tried to install an application directly onto a device. There will be support for enterprise apps in the future, but for now enterprises should stay on Windows Phone 6.5.x devices. Post Event drinks At the after event drinks gathering Scott was checking out my HTC HD2 (released to the US this month on T-Mobile) and liked the Windows Phone 6.5.5 build I have on it. We discussed why Microsoft were not going to allow Windows Phone 7 Series onto it with my understanding being that it had 5 buttons and not 3, while Scott was sure that there was more to it from a hardware standpoint. I think he is right, and although the HTC HD2 has a DX9 compatible processor, it was never built with WP7 in mind. However, as if by magic Saturday brought fantastic news for all those that have already bought an HD2: Yes, this appears to be Windows Phone 7 running on a HTC HD2. The HD2 itself won't be getting an official upgrade to Windows Phone 7 Series, so all eyes are on the ROM chefs at the moment. The rather massive photos have been posted by Tom Codon on HTCPedia and they've apparently got WiFi, GPS, Bluetooth and other bits working. The ROM isn't online yet but according to the post there's a beta version coming soon. Leigh Geary - http://www.coolsmartphone.com/news5648.html  What was Scott working on on his flight back to the US?   Technorati Tags: VS2010,MVC2,WP7S,WP7 Follow: @CAMURPHY, @ColinMackay, @plip and of course @ScottGu

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  • Windows Azure Use Case: Infrastructure Limits

    - by BuckWoody
    This is one in a series of posts on when and where to use a distributed architecture design in your organization's computing needs. You can find the main post here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx  Description: Physical hardware components take up room, use electricity, create heat and therefore need cooling, and require wiring and special storage units. all of these requirements cost money to rent at a data-center or to build out at a local facility. In some cases, this can be a catalyst for evaluating options to remove this infrastructure requirement entirely by moving to a distributed computing environment. Implementation: There are three main options for moving to a distributed computing environment. Infrastructure as a Service (IaaS) The first option is simply to virtualize the current hardware and move the VM’s to a provider. You can do this with Microsoft’s Hyper-V product or other software, build the systems and host them locally on fewer physical machines. This is a good option for canned-applications (where you have to type setup.exe) but not as useful for custom applications, as you still have to license and patch those servers, and there are hard limits on the VM sizes. Software as a Service (SaaS) If there is already software available that does what you need, it may make sense to simply purchase not only the software license but the use of it on the vendor’s servers. Microsoft’s Exchange Online is an example of simply using an offering from a vendor on their servers. If you do not need a great deal of customization, have no interest in owning or extending the source code, and need to implement a solution quickly, this is a good choice. Platform as a Service (PaaS) If you do need to write software for your environment, your next choice is a Platform as a Service such as Windows Azure. In this case you no longer manager physical or even virtual servers. You start at the code and data level of control and responsibility, and your focus is more on the design and maintenance of the application itself. In this case you own the source code and can extend or change it as you see fit. An interesting side-benefit to using Windows Azure as a PaaS is that the Application Fabric component allows a hybrid approach, which gives you a basis to allow on-premise applications to leverage distributed computing paradigms. No one solution fits every situation. It’s common to see organizations pick a mixture of on-premise, IaaS, SaaS and PaaS components. In fact, that’s a great advantage to this form of computing - choice. References: 5 Enterprise steps for adopting a Platform as a Service: http://blogs.msdn.com/b/davidmcg/archive/2010/12/02/5-enterprise-steps-for-adopting-a-platform-as-a-service.aspx?wa=wsignin1.0  Application Patterns for the Cloud: http://blogs.msdn.com/b/kashif/archive/2010/08/07/application-patterns-for-the-cloud.aspx

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  • first install for windows eight.....da beta

    - by raysmithequip
    The W8 preview is now installed and I am enjoying it.  I remember the learning curve of my first unix machine back in the eighties, this ain't that.It is normal for me to do the first os install with a keyboard and low end monitor...you never know what you'll encounter out in the field.  The OS took like a fish to water.  I used a low end INTEL motherboard dp55w I gathered on the cheap, an 1157 i5 from the used bin a pair of 6 gig ddr3 sticks, a rosewell 550 watt power supply a cheap used twenty buck sub 200g wd sata drive, a half working dvd burner and an asus fanless nvidia vid card, not a great one but Sub 50.00 on newey eggey...I did have to hunt the ms forums for a key and of course to activate the thing, if dos would of needed this outmoded ritual, we would still be on cpm and osborne would be a household name, of course little do people know that this ritual was common as far back as the seventies on att unix installs....not, but it was possible, I used to joke about when I ran a bbs, what hell would of been wrought had dos 3.2 machines been required to dial into my bbs to send fido mail to ms and wait for an acknowledgement.  All in all the thing was pushing a seven on the ms richter scale, not including the vid card, sadly it came in at just a tad over three....I wanted to evaluate it for a possible replacement on critical machines that in the past went down due to a vid card fan failure....you have no idea what a customer thinks when you show them a failed vid card fan..."you mean that little plastic piece of junk caused all this!!??!!!"...yea man.  Some production machines don't need any sort of vid, I will at least keep it on the maybe list for those, MTBF is a very important factor, some big box stores should put percentage of failure rate within 24 month estimates on the outside of the carton for sure.  And a warning that the power supplies are already at their limit.  Let's face it, today even 550w can be iffy.A few neat eye candy improvements over the earlier windows is nice, the metro screen is nice, anyone who has used a newer phone recently will intuitively drag their fingers across the screen....lot of good that was with no mouse or touch screen though.  Lucky me, I have been using windows since day one, I still have a copy of win 2.0 (and every other version) for no good reason.  Still the old ix collection of disks is much larger, recompiling any kernal is another silly ritual, same machine, different day, same recompile...argh. Rh is my all time fav, mandrake was always missing something, like it rewrote the init file or something, novell is ok as long as you stay on the beaten path and of course ubuntu normally recompiles with the same errors consistantly....makes life easy that way....no errors on windows eight, just a screen that did not match the installed hardware, natuarally I alt tabbed right out of it, then hit the flag key to find the start menu....no start button. I miss the start button already. Keyboard cowboy funnin and I was browsing the harddrive, nothing stunning there, I like that, means I can find stuff. Only I can't find what I want, the start button....the start menu is that first screen for touch tablets. No biggie for useruser, that is where they will want to be, I can see that. Admins won't want to be there, it is easy enough to get the control panel a bazzilion other ways though, just not the start button. (see a pattern here?). Personally, from the keyboard I find it fun to hit the carets along the location bar at the top of the explorer screen with tabs and arrows and choose SHOW ALL CONTROL PANEL ITEMS, or thereabouts. Bottom line, I love seven and I'll love eight even more!...very happy I did not have to follow the normal rule of thumb (a customer watching me build a system and asking questions said "oh I get it, so every piece you put in there is basically a hundred bucks, right?)...ok, sure, pretty much, more or less, well, ya dude.  It will be WAY past october till I get a real touch screen but I did pick up a pair of cheap tatungs so I can try the NEW main start screen, I parse a lot of folders and have a vision of how a pair of touch screens will be easier than landing a rover on mars.  Ok.  fine, they are way smallish, and I don't expect multitouch to work but we are talking a few percent of a new 21 inch viewsonic touch screen.  Will this OS be a game changer?  I don't know.  Bottom line with all the pads and droids in the world, it is more of a catch up move at first glance.  Not something ms is used to.  An app store?  I can see ms's motivation, the others have it.  I gather there will not be gadgets there, go ahead and see what ms did  to the once populated gadget page...go ahead, google gadgets and take a gander, used to hundreds of gadgets, they are already gone.  They replaced gadgets?  sort of, I'll drop that, it's a bit of a sore point for me.  More of interest was what happened when I downloaded stuff off codeplex and some other normal programs that I like, like orbitron, top o' my list!!...cardware it is...anyways, click on the exe, get a screen, normal for windows, this one indicated that I was not running a normal windows program and had a button for  exit the install, naw, I hit details, a hidden run program anyways came into view....great, my path to the normal windows has detected a program tha.....yea ok, acl is on, fine, moving along I got orbitron installed in record time and was tracking the iss on the newest Microsoft OS, beta of course, felt like the first time I setup bsd all those year ago...FUN!!...I suppose I gotta start to think about budgeting for the real os when it comes out in october, by then I should have a rasberry pi and be done with fedora remixed.  Of course that sounds like fun too!!  I would use this OS on a tablet or phone.  I don't like the idea of being hearded to an app store, don't like that on anything, we are americans and want real choices not marketed hype, lest you are younger with opm (other peoples money).   This os would be neat on a zune, but I suspect the zune is a gonner, I am rooting for microsoft, after all their default password is not admin anymore, nor alpine,  it's blank. Others force a password, my first fawn password was so long I could not even log into it with the password in front of me, who the heck uses %$# anyways, and if I was writing a brute force attack what the heck kinda impasse is that anyways at .00001 microseconds of a code execution cycle (just a non qualified number, not a real clock speed)....AI is where it will be before too long, MS is on that path, perhaps soon someone will sit down and write an app for the kinect that watches your eyes while you scan the new main start screen, clicking on the big E icon when you blink.....boy is that going to be fun!!!! sure. Blink,dammit,blink,dammit...... OPM no doubt.I like windows eight, we are moving forwards, better keep a close eye on ubuntu.  The real clinch comes when open source becomes paid source......don't blink, I already see plenty of very expensive 'ix apps, some even in app stores already.  more to come.......

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  • Chargeback and showback...both a 'throw back'

    - by llaszews
    Been getting asked again by customers and partners about chargeback and showback in the cloud so thought I would blog on my response to this question. Charge Back background, information and industry analysis: Cloud computing is all about shared resources. These shared resources are computer servers (including memory and CPU), network devices, hard disk storage, database servers, application servers, cooling, floor space, electricity and more. These resources are shared by departments within a company, or by a number of companies, when resources are hosted in the public or hybrid cloud. Currently, hosting providers that run other companies on their cloud platforms do not have an accurate way to measure the shared computing resources used by a specific user let alone used by a specific customer. Additionally, companies running their own cloud data centers, for private or hybrid clouds, have no way of measure and charging back the departments in the company that are using these shared cloud resources. In both cases, the lack of determine shared resource costs and to charge them back to the company, department or user that is using this resources is limited a clear measure of business benefit and impacting company’s ability to measure the Return on Investment (ROI). An IT chargeback system is an accounting strategy that applies the costs of IT services, hardware or software to the business unit in which they are used. This system contrasts with traditional IT accounting models in which a centralized department bears all of the IT costs in an organization and those costs are treated simply as corporate overhead. Showback involves showing the IT costs to a department or customer but not actually charging them for their IT usage. Showback is a gradual method of introducing chargeback into an enterprise. Most companies implement a show back mechanism before a full chargeback system is put in place. Oracle chargeback product: Oracle Enterprise Manager provides tools for defining detailed Chargeback plans spanning different metrics collected for each type of resources as well as defining Cost Centers for grouping costs across multiple developers. Chargeback plans can use not only usage based costs, but also configuration based costs (e.g. version of the platform) or fixed costs (e.g. flat-rate management fee). Chargeback has rich out of the box reports. Trending reports show how charge and resource consumption varies over time, while Summary reports show the breakdown of charges or usage by different dimensions such as Cost Center or Target Type. These reports help consumers in understanding how their charges relate to their consumption and also assist the IT department with budgeting and planning activities. With BI Publisher, the reports can be made available in a variety of formats such as PDF, HTML, Word, Excel or PowerPoint.

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  • Can I upgrade the CPU in my Lenovo 3000 N100 laptop?

    - by Pavel
    I've got an Intel Core Duo T2300 in my laptop (Lenovo 3000 N100, 0768-49G). Here is what I could find out about it: $ sudo dmidecode # dmidecode 2.11 SMBIOS 2.4 present. 42 structures occupying 1436 bytes. Table at 0x000DC010. Handle 0x0000, DMI type 0, 24 bytes BIOS Information Vendor: LENOVO Version: 61ET37WW Release Date: 06/04/07 Address: 0xE6B70 [...] Handle 0x0002, DMI type 2, 8 bytes Base Board Information Manufacturer: LENOVO Product Name: CAPELL VALLEY(NAPA) CRB [...] Handle 0x0004, DMI type 4, 35 bytes Processor Information Socket Designation: U2E1 Type: Central Processor Family: Other Manufacturer: Intel ID: E8 06 00 00 FF FB E9 BF Version: Genuine Intel(R) CPU T2300 @ 1.66GHz Voltage: 3.3 V External Clock: 166 MHz Max Speed: 2048 MHz Current Speed: 1600 MHz Status: Populated, Enabled Upgrade: ZIF Socket L1 Cache Handle: 0x0005 L2 Cache Handle: 0x0006 L3 Cache Handle: Not Provided Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified $ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 14 model name : Genuine Intel(R) CPU T2300 @ 1.66GHz stepping : 8 microcode : 0x39 cpu MHz : 1000.000 cache size : 2048 KB I believe the chipset is "Mobile Intel 945GM Express", but I don't know how to verify it on a Linux system. I'm not sure about the socket, but Intel claims "Sockets Supported: PBGA479, PPGA478". Now, I'd like to upgrade to the fastest compatible CPU available, but I'm a bit lost in all the details. Can you guys help me out with a couple of questions, please? What CPUs can I choose from? (I think it's only the Core2Duo line, but it should be enough for an upgrade) Can I use a 64-bit CPU? Can I use a CPU with a higher FSB than 667 MHz? Do I have to worry about additional cooling, or is it enough to check for similar voltage/TDP values? Thank you!

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  • Nvidia GTS 360M in Asus laptop shuts off when gaming on external display

    - by mr odus
    I have had this problem on my Asus G51j Intel I5, Nvidia GTS360M graphics card. Just updated the drivers to latest off Nvidias site. Most games I play, If I hook it up through an external monitor(this happens whether it's HDMI or VGA). The laptop hard shuts down after about 20 minutes, give or take. This tends to happen on more graphically intense games like Call of dutys, bioshock. I'm running Windows 7, latest nvidia drivers. Games work fine on my laptops screen, and Movies, general computing work fine on the external displays. The laptop always sits on a cooling pad and the latest time was in front of my AC unit, I ran heatfan or whatever the heat tracking software was, and my temperatures were normal through a shut down. This has been happening for the life of the laptop. I dont play very many games, and even fewer on an external monitor, so this issue doesnt come up much Is it possible I have a faulty graphics card? Is there anything else I can try?

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  • Getting started with webserver clustering.

    - by Ernie
    I work for a small ISP, and we host about 250 domains and all the stuff that goes along with that: DNS, mail, spam filtering, and backups. Currently, we have separate DNS servers (two of them) and mail servers (outgoing mail is actually on the secondary DNS server, but was previously on its own server). In the past, this was done as an insurance measure. The last thing we need is for some doofus (usually yours truly) to hose a server, taking out DNS and mail right along with it, or for spammers to jam our incoming SMTP server, preventing outgoing mail from being sent too. In the past, this was a problem, and our servers were set up the way they are now to combat it. However, clustering solutions like Sun's Cobalt RAQ (in days of olde) and Virtualmin appear to cater to an all-in-one approach, then deal with failures through redundant servers. I have avoided this thus far, but we've been using Virtualmin on our web server for a while now, and I'd like to expand into using it for a high availability cluster. Our networking partner has recently built a datacenter that has eliminated all of our other bugaboos like network, cooling, and power issues, so now the only thing left to go wrong is me hosing a server, which happened earlier this month. One of the bigger reasons we've avoided going this route is because our hardware requirements aren't particularly high. One server easily handles all the sites we host (most of them are flat sites). Also, load-balancing routers tend to be expensive and complicated. All that I'm really expecting to do is building a two-node cluster for redundancy so that when I hose a server (however rare that might be), we're not out for 8-12 hours while I rebuild it. What I need to know is how to get started, and if I'm really in a position to bother with this kind of thing at all.

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  • Building a PC for Work and play? [closed]

    - by Derek Organ
    Ok, Its been a long time since I build my own PC so I'm looking to get back into it again and build a new one. First off budget is about €800 excluding the monitor and windows 7 licence and mouse. (just bought a new g500) I plan on using my computer for work, lots of applications open at once but none particularly excessive (photoshop being the most demanding, mostly coding tools) I also use it for some gaming, e.g. COD, Starcraft etc. One thing I do want to do eventually is get a really good monitor with hight resolution and maybe 27" so the graphics card needs to be able to make best use of that. So a few questions 1) Is the bottle neck in performance mostly still the harddrives? 2) Aren't most processors e.g. i5 etc even i3 so far a head of other bottlenecks it makes litte difference the higher you go. Isn't the Graphics card dealing with heavy graphics so what really slows because of a slow CPU? So from this my thinking is to get a SSD drive as my primary drive for OS etc and have loads of memory e.g. 6-8GB and a decent mid level graphics card? It doesn't seem at my level worth spending much on CPU and any other parts really. I basic parts off the top of my head Case, Motherboard CPU SSD Drive SATA Drive Power Supply Memory Cooling (fan?) Graphics Card Network Card Keyboard DVD drive Mouse Windows Monitor Am I missing anything? Any helpful tips or general education much appreciated. Thanks, Derek

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  • ipmi - can't ping or remotely connect

    - by Fidel
    I've tried configuring the IPMI controller to accept remote connections, but I can't even ping it. Here is it status: #/usr/local/bin/ipmitool lan print 2 Set in Progress : Set Complete Auth Type Support : NONE PASSWORD Auth Type Enable : Callback : : User : NONE PASSWORD : Operator : PASSWORD : Admin : PASSWORD : OEM : IP Address Source : Static Address IP Address : 192.168.1.112 Subnet Mask : 255.255.255.0 MAC Address : 00:a0:a5:67:45:25 IP Header : TTL=0x40 Flags=0x40 Precedence=0x00 TOS=0x10 BMC ARP Control : ARP Responses Enabled, Gratuitous ARP Enabled Gratituous ARP Intrvl : 8.0 seconds Default Gateway IP : 192.168.1.1 Default Gateway MAC : 00:00:00:00:00:00 802.1q VLAN ID : Disabled 802.1q VLAN Priority : 0 RMCP+ Cipher Suites : 0,1,2,3 Cipher Suite Priv Max : uaaaXXXXXXXXXXX : X=Cipher Suite Unused : c=CALLBACK : u=USER : o=OPERATOR : a=ADMIN : O=OEM # /usr/local/bin/ipmitool user list 2 ID Name Enabled Callin Link Auth IPMI Msg Channel Priv Limit 1 true false true true USER 2 admin true false true true ADMINISTRATOR # /usr/local/bin/ipmitool channel getaccess 2 2 Maximum User IDs : 5 Enabled User IDs : 2 User ID : 2 User Name : admin Fixed Name : No Access Available : callback Link Authentication : enabled IPMI Messaging : enabled Privilege Level : ADMINISTRATOR # /usr/local/bin/ipmitool channel info 2 Channel 0x2 info: Channel Medium Type : 802.3 LAN Channel Protocol Type : IPMB-1.0 Session Support : multi-session Active Session Count : 0 Protocol Vendor ID : 7154 Volatile(active) Settings Alerting : disabled Per-message Auth : disabled User Level Auth : disabled Access Mode : always available Non-Volatile Settings Alerting : disabled Per-message Auth : disabled User Level Auth : disabled Access Mode : always available # /usr/local/bin/ipmitool chassis status System Power : on Power Overload : false Power Interlock : inactive Main Power Fault : false Power Control Fault : false Power Restore Policy : unknown Last Power Event : Chassis Intrusion : inactive Front-Panel Lockout : inactive Drive Fault : false Cooling/Fan Fault : false # arp Address HWtype HWaddress Flags Mask Iface 192.168.1.112 ether 00:A0:A5:67:45:25 C bond0 # /usr/local/bin/ipmitool -I lan -H 192.168.1.112 -U admin -P admin chassis power status Error: Unable to establish LAN session Unable to get Chassis Power Status In summary. It exists on the ARP list so arp's are being broadcast. I can't ping it and can't connect to it. Can anyone spot any glaring mistakes in the configuration? Many thanks, Fidel

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  • Sandra reports my CPU as "Engineering Sample", how can I be sure this is correct?

    - by stevenvh
    I ran SiSoftware's Sandra on my new PC, and for my CPU it reports: Generation : G8 / T29 Name : TN0 (Trinity) FX/Opteron 32nm (ES) Revision/Stepping : 0 : 10 / 1 Stepping Mask : TN-A1 Microcode : MU6F10010F The (ES) is a well-known code in product development, meaning "Engineering Sample". Those are beta versions of the CPU, which still may contain some bugs, or even have features switches off. I contacted both the PC's manufacturer Medion as well as AMD about this. I had to downvote the Medion helpdesk here. The person I talked to boldly said Sandra was wrong (without knowing how Sandra got this information; he didn't even know the software), and used the word "impossible". His conclusion was "We’re not taking this in consideration for service”. Right. So, if you like Medion for their good prices, but like good support even better, you may consider buying your PC elsewhere. AMD was more helpful, but wanted to be sure before replacing the part (which I find reasonable). They suggested that I dismount the cooler from the CPU to check what was printed on it to be sure. I'm a bit reluctant here: I would have to wipe the thermal paste from the CPU, and won't know for sure my cooling will still be OK afterwards. Questions Has anybody actually found a confirmed ES CPU in her PC? Is anybody aware of Sandra erroneously reporting CPUs as Engineering Samples? How can you tell an ES, apart from the print on the package? Shouldn't Stepping Mask identify the CPU uniquely?

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  • Using my old PC as a web/file server?

    - by Garrett
    I have an old desktop computer that I've been trying to sell for AGES. I guess nobody is looking for computers because it was advertised at a dirt cheap price on craigslist, local papers, etc. Anyways, I was wondering if it would be worth it to set it up as a home file server, a web dev server (I have a web host for actual production use), and maybe host a few server applications (ex: ventrillo). The computer is actually an old Dell that I cannibalized after the motherboard being destroyed by lightning, so it has fairly new parts in it. The specs are: P4 3.4GHz w/ HT and Artic Cooling Freezer 7 3GB DDR2 533 RAM 80GB hdd (will upgrade the hard drive if it's even worth using as a server) basic dvd rom 430 Watt Thermaltake PSU (it might be important to note that it is only 60% efficiency) ATI Radeon x600 256MB Antec 300 case It's not a really beefy machine, I just can't see giving it away or putting it in the corner to just collect dust. I have Windows Server 2008 R2 Standard and I am confident in my skills in operating most Linux operating systems. I'd also be using it to tinker with when I learn new things in my server admin classes (I'm finishing my 2nd year in college at the moment so I'm still learning) Also, my house is quite old and the electrical wiring is pretty poor (it MIGHT be up to code, then again, where I live most people don't even know what regulations are or let alone know how to spell it...) Would it be safe to leave it running all day and is it going to run up my electric bill because of the PSU efficiency? I only have 5mbit cable internet, but I won't be running very bandwidth intense services on it so it should be ok. I should elaborate on why I am concerned about the power. The circuits should be fine, but I'm more concerned about fire hazard. What is the likelihood that the server could cause an electrical fire? Again, thank you all for the feedback!

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  • Where is my problem? The P6X58D Premium Mobo, Windows 7, or other?

    - by Dylan Yaga
    I was having problems with my USB devices for an hour last night, and I am unable to determine the root cause of the problem. The two symptoms are: At seemingly random times (not consistently spaced by time or caused by any detectable event) my USB devices become "detached". Windows will play the USB disconnect sound and then the reconnect sound. The devices disconnected and then reconnected. My USB Keyboard will "stick" on one key for several seconds before processing any other keystroke made. The mouse also does not respond to clicks. I do not lose mouse movement or USB device connectivity. And after a moment of this several beeps will be emitted from the speakers. Hardware Specs: GFX Card: EVGA GeForce GTX 470 Superclocked 1280MB DDR5 PCIe Motherboard: ASUS P6X58D Premium Intel X58 Socket LGA1366 MB Processor: Intel Core i7-920 2.66Ghz 8M LGA1366 CPU Memory: Corsair Dominator 6144MB PC12800 DDR3 Storage: Hitachi 1TB Serial ATA HD 1600MHz 7200/32MB/SATA-3G Cooling: Corsair Hydro H50 CPU Liquid Cooler Case: Corsair Obsidian 800D Full Tower Case Power Supply: Corsair HX1000W 1000W Modular Power Supply Steps I have taken to narrow down the problem: Restarted the computer. - No change Changed USB port the Hub was connected to on the CPU. - No change Removed all devices from USB Hub and connected directly to CPU. - No change Used a different USB keyboard both in USB Hub and directly to CPU. - No change Disconnected and reconnected all cables. - No change Disassembled the Tower and determined if the USB headers were firmly connected. - No change Checked device manager for errors. Checked all USB devices. - Nothing flagged After an hour of frustration trying to narrow down the problem it appeared to disappear. But I am torn between it being a Mobo problem or an OS problem. Is there anything else I can do to narrow down the problem before a reformat and then eventually exchanging the Mobo?

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  • CPU temperatures high on new build after gaming

    - by Reznor
    My friend had a problem with his computer a while back. His games were crashing, even within the menus. He was stumped as to what the problem was, so I posted on here requesting help. He found out the day later, when his computer would start up but wouldn't display anything on the screen. His video card must have came screwed up. So, he got a replacement. Now, there's a new problem. His temperatures, which were acceptable before, are now insanely high. His GPU temperature runs 70-80c, which is understandable considering he's running his games maxed out, but the real problem here is his processor and motherboard temperatures. All four of his cores are running at 88-90c after coming out of a game. His motherboard temperature was also 70c at one point. In terms of cooling, his case should definitely be adequate. He has an Antec Twelve Hundred. He's using stock fans. The cable management in his case is very good; better than average. He's using the stock heatsink with the processor too, but note, it was fine before the replacement, so it isn't like there's some inherent problem. He has checked the case too. Everything's fine! No cables in the way. The heatsink is seated properly. He turned his case fans up to high, as well, but the temperatures are persisting. Could the processor be overheating due to running games maxed out? Any ideas?

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  • CPU operating temperature ranges

    - by osij2is
    I have an AMD Phenom II 960T with 2 cores unlocked for a total of 6 cores. I don't overclock at all. I have a Arctic Cooling ACALP64 Heatsink/Fan installed. I'm currently running ESXi 5.0 so I have to go into the BIOS to read the CPU temperatures, which at idle seem to be in the 71-74C range. To me, this is pretty high, but I cannot find any official temperature ranges that AMD says the CPU can work well within. There seems to be a lot of questions on superuser and numerous forums around CPU temperatures but no one seems to have a clear consensus as to what the manufacturer temperature ranges are for specific CPUs. I've tried searching through AMDs site to no avail. At this point, I'd be willing to shut off the 2 extra cores if it keeps the heat down but until I get some sort of tolerance or range for temperature, I have no idea if the CPU is being damaged or not. Can anyone point to a direct source, article, FAQ from AMD that specifically states their CPUs temperature range? Or are CPU temperature ranges so varying that there's no possible baseline? Am I being too paranoid about this? To me, anything over 65C is a bit much and if I'm in the low-mid 70s range with NO VMs running, what can I expect if I have several VMs running?

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  • Computer making strange sound when turned on, ever since power outage

    - by Dot NET
    Recently we experienced a power outage, and the PC was off. However, once the power came back, I switched on the PC and heard a strange noise - almost as if the hard disk or fans were struggling to work. I can't really describe the sound, but it's a laboured, loud sound almost like a jack-hammer. This has been persisting ever since the power outage, however the noise stops after around 10 minutes or so, and doesn't start again until the computer is turned off and on again. At first I thought it had something to do with the HDD, but all my files are intact, chkdsk did not report any issues and performance is 100% unchanged, even in games (so the gfx card is fine, and so is the HDD most likely). My PC setup basically has around 3 cooling fans, but I'm not sure if it's one of these either as the noise actually stops after 10 minutes or so, and if I leave the PC on for 4 hours (for example) the noise never starts again. It's there solely when turning on the PC. I haven't got a UPS, and it's important to note that the computer was not on when the power went out - it was merely plugged in. I then promptly unplugged the PC once the power was out, and only plugged it in again when the power came back. Could it be the power supply? Unfortunately I can't open my tower as I would void the warranty. Are there any tests which I could carry out without voiding the warranty?

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  • Graphics artifacts/distortion with Win7 and nVidia

    - by Gepard
    Problem I encounter is rather hard to describe, so I provide a screenshot: http://dl.dropbox.com/u/1732760/video-distortion.png As you can see there are some horizontal stripes in random colors. These stripes appear sometimes in all windowed apps, games and on the desktop too. They tend to stay in place until I refresh window (or force it to to redraw by for example minimizing and maximizing again). They also tend to appear in the same place and shape multiple times, even if they disappear, it's very likely they will be again in the same place after a while. These artifacts do not blink or change if computer is idling. If I don't touch anything, do not use mouse, they will stay in place forever (unless some app redraws its window on its own). I first encountered this problem some weeks ago. Back then I thought it might be cooling problem, so I took out the graphics card, removed dust from the radiator and fan and put it into PC back. I also ran some stress test using Furmark (peak tempearature was ~65C) to see if the problem becomes more intense if the card gets hotter, but suprisingly no artifacts whatsoever appear during the stress test. Graphic card is Galaxy GeForce 7300 GT with DDR3 memory, was never overclocked. Drivers are the latest, from Nvidia site. OS is Windows 7 64-bit, updated. AMD64 3000+, 2GB RAM. I'm running a dual monitor setup with 2 19'' Samsung LCDs and problem is on both, so I assume it's not a monitor or cable issue.

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  • Which components should I invest in.. for a backup machine.

    - by Senthil
    I am a freelance developer. I have a PC, a laptop and an old testing and file server machine. I might add one or two in future. I want to have an on-site backup machine that can handle backups of ALL these machines - file backups, MySQL backups, backup of subversion repository, etc.. When building the machine, which components should I invest more in? Examples: The cabinet should have lots of room for expansion. Hard disk size should be large. But I guess hard disk speed need not be high (?) But other components like, RAM, PSU, Processor, Network card, Cooling, etc.. how much relative importance do these have in a backup machine? Which of these components should be high-end or large, and which ones need not be? Some Idea of the load: There will TBs of data. File backups and subversion repository backups will at least be done daily. MySQL backups done weekly. assume 3 machines at the moment and somewhere around 10 machines in the future.

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  • Dell PowerEdge R410: System asks to press F1 or F2

    - by hurikhan77
    We just installed an option card (PERC 6/i) into a brand-new Dell PowerEdge R410 and now the system does no unattended startup but instead asks me to press F1 to continue or F2 to enter system setup after printing the following message on the console: Fan 4 speed may change depending on system configuration and option card install. How do I make the system ignore this "problem" or whatever that is? This system is going to be installed at a remote data center and needs to be able to restart unattended. I do not want to ignore errors completely to not get endless restart loops in case of errors.

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