Search Results

Search found 30217 results on 1209 pages for 'website performance'.

Page 375/1209 | < Previous Page | 371 372 373 374 375 376 377 378 379 380 381 382  | Next Page >

• Organization &amp; Architecture UNISA Studies &ndash; Chap 6

  - by MarkPearl

  Learning Outcomes Discuss the physical characteristics of magnetic disks Describe how data is organized and accessed on a magnetic disk Discuss the parameters that play a role in the performance of magnetic disks Describe different optical memory devices Magnetic Disk The way data is stored on and retried from magnetic disks Data is recorded on and later retrieved form the disk via a conducting coil named the head (in many systems there are two heads) The writ mechanism exploits the fact that electricity flowing through a coil produces a magnetic field. Electric pulses are sent to the write head, and the resulting magnetic patterns are recorded on the surface below with different patterns for positive and negative currents The physical characteristics of a magnetic disk   Summarize from book   The factors that play a role in the performance of a disk Seek time – the time it takes to position the head at the track Rotational delay / latency – the time it takes for the beginning of the sector to reach the head Access time – the sum of the seek time and rotational delay Transfer time – the time it takes to transfer data RAID The rate of improvement in secondary storage performance has been considerably less than the rate for processors and main memory. Thus secondary storage has become a bit of a bottleneck. RAID works on the concept that if one disk can be pushed so far, additional gains in performance are to be had by using multiple parallel components. Points to note about RAID… RAID is a set of physical disk drives viewed by the operating system as a single logical drive Data is distributed across the physical drives of an array in a scheme known as striping Redundant disk capacity is used to store parity information, which guarantees data recoverability in case of a disk failure (not supported by RAID 0 or RAID 1) Interesting to note that the increase in the number of drives, increases the probability of failure. To compensate for this decreased reliability RAID makes use of stored parity information that enables the recovery of data lost due to a disk failure.   The RAID scheme consists of 7 levels…   Category Level Description Disks Required Data Availability Large I/O Data Transfer Capacity Small I/O Request Rate Striping 0 Non Redundant N Lower than single disk Very high Very high for both read and write Mirroring 1 Mirrored 2N Higher than RAID 2 – 5 but lower than RAID 6 Higher than single disk Up to twice that of a signle disk for read Parallel Access 2 Redundant via Hamming Code N + m Much higher than single disk Highest of all listed alternatives Approximately twice that of a single disk Parallel Access 3 Bit interleaved parity N + 1 Much higher than single disk Highest of all listed alternatives Approximately twice that of a single disk Independent Access 4 Block interleaved parity N + 1 Much higher than single disk Similar to RAID 0 for read, significantly lower than single disk for write Similar to RAID 0 for read, significantly lower than single disk for write Independent Access 5 Block interleaved parity N + 1 Much higher than single disk Similar to RAID 0 for read, lower than single disk for write Similar to RAID 0 for read, generally  lower than single disk for write Independent Access 6 Block interleaved parity N + 2 Highest of all listed alternatives Similar to RAID 0 for read; lower than RAID 5 for write Similar to RAID 0 for read, significantly lower than RAID 5  for write   Read page 215 – 221 for detailed explanation on RAID levels Optical Memory There are a variety of optical-disk systems available. Read through the table on page 222 – 223 Some of the devices include… CD CD-ROM CD-R CD-RW DVD DVD-R DVD-RW Blue-Ray DVD Magnetic Tape Most modern systems use serial recording – data is lade out as a sequence of bits along each track. The typical recording used in serial is referred to as serpentine recording. In this technique when data is being recorded, the first set of bits is recorded along the whole length of the tape. When the end of the tape is reached the heads are repostioned to record a new track, and the tape is again recorded on its whole length, this time in the opposite direction. That process continued back and forth until the tape is full. To increase speed, the read-write head is capable of reading and writing a number of adjacent tracks simultaneously. Data is still recorded serially along individual tracks, but blocks in sequence are stored on adjacent tracks as suggested. A tape drive is a sequential access device. Magnetic tape was the first kind of secondary memory. It is still widely used as the lowest-cost, slowest speed member of the memory hierarchy.

  Read the article

• Efficiently separating Read/Compute/Write steps for concurrent processing of entities in Entity/Component systems

  - by TravisG

  Setup I have an entity-component architecture where Entities can have a set of attributes (which are pure data with no behavior) and there exist systems that run the entity logic which act on that data. Essentially, in somewhat pseudo-code: Entity { id; map<id_type, Attribute> attributes; } System { update(); vector<Entity> entities; } A system that just moves along all entities at a constant rate might be MovementSystem extends System { update() { for each entity in entities position = entity.attributes["position"]; position += vec3(1,1,1); } } Essentially, I'm trying to parallelise update() as efficiently as possible. This can be done by running entire systems in parallel, or by giving each update() of one system a couple of components so different threads can execute the update of the same system, but for a different subset of entities registered with that system. Problem In reality, these systems sometimes require that entities interact(/read/write data from/to) each other, sometimes within the same system (e.g. an AI system that reads state from other entities surrounding the current processed entity), but sometimes between different systems that depend on each other (i.e. a movement system that requires data from a system that processes user input). Now, when trying to parallelize the update phases of entity/component systems, the phases in which data (components/attributes) from Entities are read and used to compute something, and the phase where the modified data is written back to entities need to be separated in order to avoid data races. Otherwise the only way (not taking into account just "critical section"ing everything) to avoid them is to serialize parts of the update process that depend on other parts. This seems ugly. To me it would seem more elegant to be able to (ideally) have all processing running in parallel, where a system may read data from all entities as it wishes, but doesn't write modifications to that data back until some later point. The fact that this is even possible is based on the assumption that modification write-backs are usually very small in complexity, and don't require much performance, whereas computations are very expensive (relatively). So the overhead added by a delayed-write phase might be evened out by more efficient updating of entities (by having threads work more % of the time instead of waiting). A concrete example of this might be a system that updates physics. The system needs to both read and write a lot of data to and from entities. Optimally, there would be a system in place where all available threads update a subset of all entities registered with the physics system. In the case of the physics system this isn't trivially possible because of race conditions. So without a workaround, we would have to find other systems to run in parallel (which don't modify the same data as the physics system), other wise the remaining threads are waiting and wasting time. However, that has disadvantages Practically, the L3 cache is pretty much always better utilized when updating a large system with multiple threads, as opposed to multiple systems at once, which all act on different sets of data. Finding and assembling other systems to run in parallel can be extremely time consuming to design well enough to optimize performance. Sometimes, it might even not be possible at all because a system just depends on data that is touched by all other systems. Solution? In my thinking, a possible solution would be a system where reading/updating and writing of data is separated, so that in one expensive phase, systems only read data and compute what they need to compute, and then in a separate, performance-wise cheap, write phase, attributes of entities that needed to be modified are finally written back to the entities. The Question How might such a system be implemented to achieve optimal performance, as well as making programmer life easier? What are the implementation details of such a system and what might have to be changed in the existing EC-architecture to accommodate this solution?

  Read the article

• The Best Data Integration for Exadata Comes from Oracle

  - by maria costanzo

  Oracle Data Integrator and Oracle GoldenGate offer unique and optimized data integration solutions for Oracle Exadata. For example, customers that choose to feed their data warehouse or reporting database with near real-time throughout the day, can do so without decreasing  performance or availability of source and target systems. And if you ask why real-time, the short answer is: in today’s fast-paced, always-on world, business decisions need to use more relevant, timely data to be able to act fast and seize opportunities. A longer response to "why real-time" question can be found in a related blog post. If we look at the solution architecture, as shown on the diagram below,  Oracle Data Integrator and Oracle GoldenGate are both uniquely designed to take full advantage of the power of the database and to eliminate unnecessary middle-tier components. Oracle Data Integrator (ODI) is the best bulk data loading solution for Exadata. ODI is the only ETL platform that can leverage the full power of Exadata, integrate directly on the Exadata machine without any additional hardware, and by far provides the simplest setup and fastest overall performance on an Exadata system. We regularly see customers achieving a 5-10 times boost when they move their ETL to ODI on Exadata. For  some companies the performance gain is even much higher. For example a large insurance company did a proof of concept comparing ODI vs a traditional ETL tool (one of the market leaders) on Exadata. The same process that was taking 5hrs and 11 minutes to complete using the competing ETL product took 7 minutes and 20 seconds with ODI. Oracle Data Integrator was 42 times faster than the conventional ETL when running on Exadata.This shows that Oracle's own data integration offering helps you to gain the most out of your Exadata investment with a truly optimized solution. GoldenGate is the best solution for streaming data from heterogeneous sources into Exadata in real time. Oracle GoldenGate can also be used together with Data Integrator for hybrid use cases that also demand non-invasive capture, high-speed real time replication. Oracle GoldenGate enables real-time data feeds from heterogeneous sources non-invasively, and delivers to the staging area on the target Exadata system. ODI runs directly on Exadata to use the database engine power to perform in-database transformations. Enterprise Data Quality is integrated with Oracle Data integrator and enables ODI to load trusted data into the data warehouse tables. Only Oracle can offer all these technical benefits wrapped into a single intelligence data warehouse solution that runs on Exadata. Compared to traditional ETL with add-on CDC this solution offers: §  Non-invasive data capture from heterogeneous sources and avoids any performance impact on source §  No mid-tier; set based transformations use database power §  Mini-batches throughout the day –or- bulk processing nightly which means maximum availability for the DW §  Integrated solution with Enterprise Data Quality enables leveraging trusted data in the data warehouse In addition to Starwood Hotels and Resorts, Morrison Supermarkets, United Kingdom’s fourth-largest food retailer, has seen the power of this solution for their new BI platform and shared their story with us. Morrisons needed to analyze data across a large number of manufacturing, warehousing, retail, and financial applications with the goal to achieve single view into operations for improved customer service. The retailer deployed Oracle GoldenGate and Oracle Data Integrator to bring new data into Oracle Exadata in near real-time and replicate the data into reporting structures within the data warehouse—extending visibility into operations. Using Oracle's data integration offering for Exadata, Morrisons produced financial reports in seconds, rather than minutes, and improved staff productivity and agility. You can read more about Morrison’s success story here and hear from Starwood here. From an Irem Radzik article.

  Read the article

• Blink-Data vs Instinct?

  - by Samantha.Y. Ma

  In his landmark bestseller Blink, well-known author and journalist Malcolm Gladwell explores how human beings everyday make seemingly instantaneous choices --in the blink of an eye--and how we “think without thinking.”  These situations actually aren’t as simple as they seem, he postulates; and throughout the book, Gladwell seeks answers to questions such as: 1.    What makes some people good at thinking on their feet and making quick spontaneous decisions?2.    Why do some people follow their instincts and win, while others consistently seem to stumble into error?3.    Why are some of the best decisions often those that are difficult to explain to others?In Blink, Gladwell introduces us to the psychologist who has learned to predict whether a marriage will last, based on a few minutes of observing a couple; the tennis coach who knows when a player will double-fault before the racket even makes contact with the ball; the antiquities experts who recognize a fake at a glance. Ultimately, Blink reveals that great decision makers aren't those who spend the most time deliberating or analyzing information, but those who focus on key factors among an overwhelming number of variables-- i.e., those who have perfected the art of "thin-slicing.” In Data vs. Instinct: Perfecting Global Sales Performance, a new report sponsored by Oracle, the Economist Intelligence Unit (EIU) explores the roles data and instinct play in decision-making by sales managers and discusses how sales executives can increase sales performance through more effective  territory planning and incentive/compensation strategies.If you are a sales executive, ask yourself this:  “Do you rely on knowledge (data) when you plan out your sales strategy?  If you rely on data, how do you ensure that your data sources are reliable, up-to-date, and complete?  With the emergence of social media and the proliferation of both structured and unstructured data, how do you know that you are applying your information/data correctly and in-context?  Three key findings in the report are:•    Six out of ten executives say they rely more on data than instinct to drive decisions. •    Nearly one half (48 percent) of incentive compensation plans do not achieve the desired results. •    Senior sales executives rely more on current and historical data than on forecast data. Strikingly similar to what Gladwell concludes in Blink, the report’s authors succinctly sum up their findings: "The best outcome is a combination of timely information, insightful predictions, and support data."Applying this insight is crucial to creating a sound sales plan that drives alignment and results.  In the area of sales performance management, “territory programs and incentive compensation continue to present particularly complex challenges in an increasingly globalized market," say the report’s authors. "It behooves companies to get a better handle on translating that data into actionable and effective plans." To help solve this challenge, CRM Oracle Fusion integrates forecasting, quotas, compensation, and territories into a single system.   For example, Oracle Fusion CRM provides a natural integration between territories, which define the sales targets (e.g., collection of accounts) for the sales force, and quotas, which quantify the sales targets. In fact, territory hierarchy is a core analytic dimension to slice and dice sales results, using sales analytics and alerts to help you identify where problems are occurring. This makes territoriesStart tapping into both data and instinct effectively today with Oracle Fusion CRM.   Here is a short video to provide you with a snapshot of how it can help you optimize your sales performance.  

  Read the article

• JavaOne 2012: Nashorn Edition

  - by $utils.escapeXML($entry.author)

  As with my JavaOne 2012: OpenJDK Edition post a while back (now updated to reflect the schedule of the talks), I find it convenient to have my JavaOne schedule ordered by subjects of interest. Beside OpenJDK in all its flavors, another subject I find very exciting is Nashorn. I blogged about the various material on Nashorn in the past, and we interviewed Jim Laskey, the Project Lead on Project Nashorn in the Java Spotlight podcast. So without further ado, here are the JavaOne 2012 talks and BOFs with Nashorn in their title, or abstract:CON5390 - Nashorn: Optimizing JavaScript and Dynamic Language Execution on the JVM - Monday, Oct 1, 8:30 AM - 9:30 AMThere are many implementations of JavaScript, meant to run either on the JVM or standalone as native code. Both approaches have their respective pros and cons. The Oracle Nashorn JavaScript project is based on the former approach. This presentation goes through the performance work that has gone on in Oracle’s Nashorn JavaScript project to date in order to make JavaScript-to-bytecode generation for execution on the JVM feasible. It shows that the new invoke dynamic bytecode gets us part of the way there but may not quite be enough. What other tricks did the Nashorn project use? The presentation also discusses future directions for increased performance for dynamic languages on the JVM, covering proposed enhancements to both the JVM itself and to the bytecode compiler.CON4082 - Nashorn: JavaScript on the JVM - Monday, Oct 1, 3:00 PM - 4:00 PMThe JavaScript programming language has been experiencing a renaissance of late, driven by the interest in HTML5. Nashorn is a JavaScript engine implemented fully in Java on the JVM. It is based on the Da Vinci Machine (JSR 292) and will be available with JDK 8. This session describes the goals of Project Nashorn, gives a top-level view of how it all works, provides the current status, and demonstrates examples of JavaScript and Java working together.BOF4763 - Meet the Nashorn JavaScript Team - Tuesday, Oct 2, 4:30 PM - 5:15 PMCome to this session to meet the Oracle JavaScript (Project Nashorn) language teamBOF6661 - Nashorn, Node, and Java Persistence - Tuesday, Oct 2, 5:30 PM - 6:15 PMWith Project Nashorn, developers will have a full and modern JavaScript engine available on the JVM. In addition, they will have support for running Node applications with Node.jar. This unique combination of capabilities opens the door for best-of-breed applications combining Node with Java SE and Java EE. In this session, you’ll learn about Node.jar and how it can be combined with Java EE components such as EclipseLink JPA for rich Java persistence. You’ll also hear about all of Node.jar’s mapping, caching, querying, performance, and scaling features.CON10657 - The Polyglot Java VM and Java Middleware - Thursday, Oct 4, 12:30 PM - 1:30 PMIn this session, Red Hat and Oracle discuss the impact of polyglot programming from their own unique perspectives, examining non-Java languages that utilize Oracle’s Java HotSpot VM. You’ll hear a discussion of topics relating to Ruby, Lisp, and Clojure and the intersection of other languages where they may touch upon individual frameworks and projects, and you’ll get perspectives on JavaScript via the Nashorn Project, an upcoming JavaScript engine, developed fully in Java.CON5251 - Putting the Metaobject Protocol to Work: Nashorn’s Java Bindings - Thursday, Oct 4, 2:00 PM - 3:00 PMProject Nashorn is Oracle’s new JavaScript runtime in Java 8. Being a JavaScript runtime running on the JVM, it provides integration with the underlying runtime by enabling JavaScript objects to manipulate Java objects, implement Java interfaces, and extend Java classes. Nashorn is invokedynamic-based, and for its Java integration, it does away with the concept of wrapper objects in favor of direct virtual machine linking to Java objects’ methods provided by a metaobject protocol, providing much higher performance than what could be expected from a scripting runtime. This session looks at the details of the integration, a topic of interest to other language implementers on the JVM and a wider audience of developers who want to understand how Nashorn works.That's 6 sessions tooting the Nashorn this year at JavaOne, up from 2 last year.

  Read the article

• Drive

  - by erikanollwebb

  Picking up where we left off, let's summarize.  People have both intrinsic motivation and extrinsic motivation, and whether reward works depends a bit on what you are rewarding.  Rewards don't decreased intrinsic motivation provided you know what you are getting and why, and when you reward high performance.  But as anyone who has watched the great animation of Dan Pink's TED talk knows, even that doesn't tell the whole story.  Although people may not be less intrinsically motivated by rewards, the impact of rewards on actual performance is a really odd questions.  Larger rewards don't necessarily lead to better performance and in fact, some times lead to worse performance.  Pink argues that people are driven and engaged when they have autonomy, mastery and purpose.  If they can self-direct and can be good at what they do and have a sense of purpose for what they are doing, they show the highest engagement.   (Personally, I would add progress to the list.  My experience is that if you have autonomy, mastery and a sense of purpose but don't get a feeling that you are making any progress day to day, your level of engagement will drop rapidly.) So Pink is arguing if we could set up work so that people have a sense of purpose in what they do, have some autonomy and the ability to build mastery, you'll have better companies.  And that's probably true in a lot of ways, but there's a problem.  Sometimes, you have things you need to do but maybe you don't really want to do.  Or that you don't really see the point of.  Or that doesn't have a lot of value to you at the end of the day.  Then what does a company do?  Let me give you an example.  I've worked on some customer relationship management (CRM) tools over the years and done user research with sales people to try and understand their world.  And there's a funny thing about sales tools in CRM.  Sometimes what the company wants a sales person to do is at odds with what a sales person thinks is useful to them.  For example, companies would like to know who a sales person talked to at the company and the person level.  They'd like to know what they talked about, when, and whether the deals closed.  Those metrics would help you build a better sales force and understand what works and what does not.  But sales people see that as busy work that doesn't add any value to their ability to sell.  So you have a sales person who has a lot of autonomy, they like to do things that improve their ability to sell and they usually feel a sense of purpose--the group is trying to make a quota!  That quota will help the company succeed!  But then you have tasks that they don't think fit into that equation.  The company would like to know more about what makes them successful and get metrics on what they do and frankly, have a record of what they do in case they leave, but the sales person thinks it's a waste of time to put all that information into a sales application. They have drive, just not for all the things the company would like.   You could punish them for not entering the information, or you could try to reward them for doing it, but you still have an imperfect model of engagement.  Ideally, you'd like them to want to do it.  If they want to do it, if they are motivated to do it, then the company wins.  If *something* about it is rewarding to them, then they are more engaged and more likely to do it.  So the question becomes, how do you create that interest to do something?

  Read the article

• Concurrent Affairs

  - by Tony Davis

  I once wrote an editorial, multi-core mania, on the conundrum of ever-increasing numbers of processor cores, but without the concurrent programming techniques to get anywhere near exploiting their performance potential. I came to the.controversial.conclusion that, while the problem loomed for all procedural languages, it was not a big issue for the vast majority of programmers. Two years later, I still think most programmers don't concern themselves overly with this issue, but I do think that's a bigger problem than I originally implied. Firstly, is the performance boost from writing code that can fully exploit all available cores worth the cost of the additional programming complexity? Right now, with quad-core processors that, at best, can make our programs four times faster, the answer is still no for many applications. But what happens in a few years, as the number of cores grows to 100 or even 1000? At this point, it becomes very hard to ignore the potential gains from exploiting concurrency. Possibly, I was optimistic to assume that, by the time we have 100-core processors, and most applications really needed to exploit them, some technology would be around to allow us to do so with relative ease. The ideal solution would be one that allows programmers to forget about the problem, in much the same way that garbage collection removed the need to worry too much about memory allocation. From all I can find on the topic, though, there is only a remote likelihood that we'll ever have a compiler that takes a program written in a single-threaded style and "auto-magically" converts it into an efficient, correct, multi-threaded program. At the same time, it seems clear that what is currently the most common solution, multi-threaded programming with shared memory, is unsustainable. As soon as a piece of state can be changed by a different thread of execution, the potential number of execution paths through your program grows exponentially with the number of threads. If you have two threads, each executing n instructions, then there are 2^n possible "interleavings" of those instructions. Of course, many of those interleavings will have identical behavior, but several won't. Not only does this make understanding how a program works an order of magnitude harder, but it will also result in irreproducible, non-deterministic, bugs. And of course, the problem will be many times worse when you have a hundred or a thousand threads. So what is the answer? All of the possible alternatives require a change in the way we write programs and, currently, seem to be plagued by performance issues. Software transactional memory (STM) applies the ideas of database transactions, and optimistic concurrency control, to memory. However, working out how to break down your program into sufficiently small transactions, so as to avoid contention issues, isn't easy. Another approach is concurrency with actors, where instead of having threads share memory, each thread runs in complete isolation, and communicates with others by passing messages. It simplifies concurrent programs but still has performance issues, if the threads need to operate on the same large piece of data. There are doubtless other possible solutions that I haven't mentioned, and I would love to know to what extent you, as a developer, are considering the problem of multi-core concurrency, what solution you currently favor, and why. Cheers, Tony.

  Read the article

• Applications on the Web/Cloud the way to go? over Desktop apps?

  - by jiewmeng

  i am currently a mainly web developer, but is quite attracted to the performance and great integration with the OS (eg. Windows 7, Jump Lists, Taskbar Thumbnails, etc) something like WPF/C# can provide to the user, improving workflow and productivity. privacy and performance seems like a major downside of web/cloud apps compared to desktop apps. applications on the cloud/web work on the go, increased popularity of smartphones/netbooks majority of users may not benefit as much from increased performance of desktop apps, eg. internet surfing, word processing, probably benefit more from decreased startup times, lower costs and data on the cloud desktop applications increased performance benefits power users like 3D rendering, HD video/photo editing, gamers (i wonder if such processing maybe offset to cloud processing) integration with OS increases productivity (maybe such features can be adapted to a web version? maybe with a local desktop app to work with Web App API) more control over privacy (maybe fixed by encryption?) local data access (esp. large files) guaranteed and fast (YouTube HD fast enough most of the time) work not affected by intermittent/slow/availability internet connections (i know this is changing tho) what do you think?

  Read the article

• Surprising results with .NET multi-theading algorithm

  - by Myles J

  Hi, I've recently wrote a C# console time tabling algorithm that is based on a combination of a genetic algorithm with a few brute force routines thrown in. The initial results were promising but I figured I could improve the performance by splitting the brute force routines up to run in parallel on multi processor architectures. To do this I used the well documented Producer/Consumer model (as documented in this fantastic article http://www.albahari.com/threading/part2.aspx#_ProducerConsumerQWaitHandle). I changed my code to create one thread per logical processor during the brute force routines. The performance gains on my work station were very pleasing. I am running Windows XP on the following hardware: Intel Core 2 Quad CPU 2.33 GHz 3.49 GB RAM Initial tests indicated average performance gains of approx 40% when using 4 threads. The next step was to deploy the new multi-threading version of the algorithm to our higher spec UAT server. Here is the spec of our UAT server: Windows 2003 Server R2 Enterprise x64 8 cpu (Quad-Core) AMD Opteron 2.70 GHz 255 GB RAM After running the first round of tests we were all extremely surprised to find that the algorithm actually runs slower on the high spec W2003 server than on my local XP work station! In fact the tests seem to indicate that it doesn't matter how many threads are generated (tests were ran with the app spawning between 2 to 32 threads). The algorithm always runs significantly slower on the UAT W2003 server? How could this be? Surely the app should run faster on a 8 cpu (Quad-Core) than my 2 Quad work station? Why are we seeing no performance gains with the multi-threading on the W2003 server whilst the XP workstation tests show gains of up to 40%? Any help or pointers would be appreciated. Regards Myles

  Read the article

• How to simply a foreach iteration using reflection

  - by Priya

  Consider that I have to get the overall performance of X. X has Y elements and Y in turn has Z elements which inturn has some N elements. To get the performance of X I do this: List<double> XQ = new List<double>(); foreach (Elem Y in X.Y){ List<double> YQ = new List<double>(); foreach (Elem Z in Y.Z){ List<double> ZQ = new List<double>(); foreach (Elem N in Z.N){ ZQ.Add(GetPerformance(N)); } YQ.Add(AVG(ZQ)); } XQ.Add(AVG(YQ)); } AVG of XQ list gives the performance of X. The performance can be calculated for either X or Y or for Z. X, Y and Z share the same base class. So depending on the item given the foreach loop has to be executed. Currently I have a switch case to determine each item (X or Y or Z) and the foreach loop is repeated in the code pertaining to the item (eg. If Y foreach starts from Y.Z). Is is possible to convert this whole code generic using reflection instead of having to repeat it in each switch case? Thanks

  Read the article

• Slow Python HTTP server on localhost

  - by Abiel

  I am experiencing some performance problems when creating a very simple Python HTTP server. The key issue is that performance is varying depending on which client I use to access it, where the server and all clients are being run on the local machine. For instance, a GET request issued from a Python script (urllib2.urlopen('http://localhost/').read()) takes just over a second to complete, which seems slow considering that the server is under no load. Running the GET request from Excel using MSXML2.ServerXMLHTTP also feels slow. However, requesting the data Google Chrome or from RCurl, the curl add-in for R, yields an essentially instantaneous response, which is what I would expect. Adding further to my confusion is that I do not experience any performance problems for any client when I am on my computer at work (the performance problems are on my home computer). Both systems run Python 2.6, although the work computer runs Windows XP instead of 7. Below is my very simple server example, which simply returns 'Hello world' for any get request. from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer class MyHandler(BaseHTTPRequestHandler): def do_GET(self): print("Just received a GET request") self.send_response(200) self.send_header("Content-type", "text/html") self.end_headers() self.wfile.write('Hello world') return def log_request(self, code=None, size=None): print('Request') def log_message(self, format, *args): print('Message') if __name__ == "__main__": try: server = HTTPServer(('localhost', 80), MyHandler) print('Started http server') server.serve_forever() except KeyboardInterrupt: print('^C received, shutting down server') server.socket.close() Note that in MyHandler I override the log_request() and log_message() functions. The reason is that I read that a fully-qualified domain name lookup performed by one of these functions might be a reason for a slow server. Unfortunately setting them to just print a static message did not solve my problem. Also, notice that I have put in a print() statement as the first line of the do_GET() routine in MyHandler. The slowness occurs prior to this message being printed, meaning that none of the stuff that comes after it is causing a delay.

  Read the article

• duplicate rows in join table with has_many => through and accepts_nested_attributes_for

  - by shalako

  An event has many artists, and an artist has many events. The join of an artist and an event is called a performance. I want to add artists to an event. This works except that I'm getting duplicate entries into my join table when creating a new event. This causes problems elsewhere. event.rb has_many :performances, :dependent => :destroy has_many :artists, :through => :performances accepts_nested_attributes_for :artists, :reject_if => proc {|a| a['name'].blank?} accepts_nested_attributes_for :performances, :reject_if => proc { |a| a['artist_id'].blank? }, :allow_destroy => true artist.rb has_many :performances, :dependent => :destroy has_many :artists, :through => :performances performance.rb belongs_to :artist belongs_to :event events_controller.rb def new @event = Event.new @event.artists.build respond_to do |format| format.html # new.html.erb format.xml { render :xml => @event } end end def create @event = Event.new(params[:event]) respond_to do |format| if @event.save flash[:notice] = 'Event was successfully created.' format.html { redirect_to(admin_events_url) } format.xml { render :xml => @event, :status => :created, :location => @event } else format.html { render :action => "new" } format.xml { render :xml => @event.errors, :status => :unprocessable_entity } end end end output Performance Create (0.2ms) INSERT INTO `performances` (`event_id`, `artist_id`) VALUES(7, 19) Performance Create (0.1ms) INSERT INTO `performances` (`event_id`, `artist_id`) VALUES(7, 19)

  Read the article

• genStrAsCharArray optimisation benefits

  - by Rich

  Hi I am looking into the options available to me for optimising the performance of JBoss 5.1.0. One of the options I am looking at is setting genStrAsCharArray to true in <JBOSS_HOME>/server/<PROFILE>/deployers/jbossweb.deployer/web.xml. This affects the generation of .java code from .JSPs. The comment describes this flag as: Should text strings be generated as char arrays, to improve performance in some cases? I have a few questions about this. Is this the generation of Strings in the dynamic parts of the JSP page (ie each time the page is called) or is it the generation of Strings in the static parts (ie when the .java is built from the JSP)? "in some cases" - which cases are these? What are the situations where the performance is worse? Does this speed up the generation of the .java, the compilation of the .class or the execution of the .class? At a more technical level (and the answer to this will probably depend on the answer to part 1), why can the use of char arrays improve performance? Thanks in advance Rich

  Read the article

• Oracle Enterprise Manager 11g Application Management Suite for Oracle E-Business Suite Now Available

  - by chung.wu

  Oracle Enterprise Manager 11g Application Management Suite for Oracle E-Business Suite is now available. The management suite combines features that were available in the standalone Application Management Pack for Oracle E-Business Suite and Application Change Management Pack for Oracle E-Business Suite with Oracle's market leading real user monitoring and configuration management capabilities to provide the most complete solution for managing E-Business Suite applications. The features that were available in the standalone management packs are now packaged into Oracle E-Business Suite Plug-in 4.0, which is now fully certified with Oracle Enterprise Manager 11g Grid Control. This latest plug-in extends Grid Control with E-Business Suite specific management capabilities and features enhanced change management support. In addition, this latest release of Application Management Suite for Oracle E-Business Suite also includes numerous real user monitoring improvements. General Enhancements This new release of Application Management Suite for Oracle E-Business Suite offers the following key capabilities: Oracle Enterprise Manager 11g Grid Control Support: All components of the management suite are certified with Oracle Enterprise Manager 11g Grid Control. Built-in Diagnostic Ability: This release has numerous major enhancements that provide the necessary intelligence to determine if the product has been installed and configured correctly. There are diagnostics for Discovery, Cloning, and User Monitoring that will validate if the appropriate patches, privileges, setups, and profile options have been configured. This feature improves the setup and configuration time to be up and operational. Lifecycle Automation Enhancements Application Management Suite for Oracle E-Business Suite provides a centralized view to monitor and orchestrate changes (both functional and technical) across multiple Oracle E-Business Suite systems. In this latest release, it provides even more control and flexibility in managing Oracle E-Business Suite changes.Change Management: Built-in Diagnostic Ability: This latest release has numerous major enhancements that provide the necessary intelligence to determine if the product has been installed and configured correctly. There are diagnostics for Customization Manager, Patch Manager, and Setup Manager that will validate if the appropriate patches, privileges, setups, and profile options have been configured. Enhancing the setup time and configuration time to be up and operational. Customization Manager: Multi-Node Custom Application Registration: This feature automates the process of registering and validating custom products/applications on every node in a multi-node EBS system. Public/Private File Source Mappings and E-Business Suite Mappings: File Source Mappings & E-Business Suite Mappings can be created and marked as public or private. Only the creator/owner can define/edit his/her own mappings. Users can use public mappings, but cannot edit or change settings. Test Checkout Command for Versions: This feature allows you to test/verify checkout commands at the version level within the File Source Mapping page. Prerequisite Patch Validation: You can specify prerequisite patches for Customization packages and for Release 12 Oracle E-Business Suite packages. Destination Path Population: You can now automatically populate the Destination Path for common file types during package construction. OAF File Type Support: Ability to package Oracle Application Framework (OAF) customizations and deploy them across multiple Oracle E-Business Suite instances. Extended PLL Support: Ability to distinguish between different types of PLLs (that is, Report and Forms PLL files). Providing better granularity when managing PLL objects. Enhanced Standard Checker: Provides greater and more comprehensive list of coding standards that are verified during the package build process (for example, File Driver exceptions, Java checks, XML checks, SQL checks, etc.) HTML Package Readme: The package Readme is in HTML format and includes the file listing. Advanced Package Search Capabilities: The ability to utilize more criteria within the advanced search package (that is, Public, Last Updated by, Files Source Mapping, and E-Business Suite Mapping). Enhanced Package Build Notifications: More detailed information on the results of a package build process. Better, more detailed troubleshooting guidance in the event of build failures. Patch Manager:Staged Patches: Ability to run Patch Manager with no external internet access. Customer can download Oracle E-Business Suite patches into a shared location for Patch Manager to access and apply. Supports highly secured production environments that prohibit external internet connections. Support for Superseded Patches: Automatic check for superseded patches. Allows users to easily add superseded patches into the Patch Run. More comprehensive and correct Patch Runs. Removes many manual and laborious tasks, frees up Apps DBAs for higher value-added tasks. Automatic Primary Node Identification: Users can now specify which is the "primary node" (that is, which node hosts the Shared APPL_TOP) during the Patch Run interview process, available for Release 12 only. Setup Manager:Preview Extract Results: Ability to execute an extract in "proof mode", and examine the query results, to determine accuracy. Used in conjunction with the "where" clause in Advanced Filtering. This feature can provide better and more accurate fine tuning of extracts. Use Uploaded Extracts in New Projects: Ability to incorporate uploaded extracts in new projects via new LOV fields in package construction. Leverages the Setup Manager repository to access extracts that have been uploaded. Allows customer to reuse uploaded extracts to provision new instances. Re-use Existing (that is, historical) Extracts in New Projects: Ability to incorporate existing extracts in new projects via new LOV fields in package construction. Leverages the Setup Manager repository to access point-in-time extracts (snapshots) of configuration data. Allows customer to reuse existing extracts to provision new instances. Allows comparative historical reporting of identical APIs, executed at different times. Support for BR100 formats: Setup Manager can now automatically produce reports in the BR100 format. Native support for industry standard formats. Concurrent Manager API Support: General Foundation now provides an API for management of "Concurrent Manager" configuration data. Ability to migrate Concurrent Managers from one instance to another. Complete the setup once and never again; no need to redefine the Concurrent Managers. User Experience Management Enhancements Application Management Suite for Oracle E-Business Suite includes comprehensive capabilities for user experience management, supporting both real user and synthetic transaction based user monitoring techniques. This latest release of the management suite include numerous improvements in real user monitoring support. KPI Reporting: Configurable decimal precision for reporting of KPI and SLA values. By default, this is two decimal places. KPI numerator and denominator information. It is now possible to view KPI numerator and denominator information, and to have it available for export. Content Messages Processing: The application content message facility has been extended to distinguish between notifications and errors. In addition, it is now possible to specify matching rules that can be used to refine a selected content message specification. Note this is only available for XPath-based (not literal) message contents. Data Export: The Enriched data export facility has been significantly enhanced to provide improved performance and accessibility. Data is no longer stored within XML-based files, but is now stored within the Reporter database. However, it is possible to configure an alternative database for its storage. Access to the export data is through SQL. With this enhancement, it is now more easy than ever to use tools such as Oracle Business Intelligence Enterprise Edition to analyze correlated data collected from real user monitoring and business data sources. SNMP Traps for System Events: Previously, the SNMP notification facility was only available for KPI alerting. It has now been extended to support the generation of SNMP traps for system events, to provide external health monitoring of the RUEI system processes. Performance Improvements: Enhanced dashboard performance. The dashboard facility has been enhanced to support the parallel loading of items. In the case of dashboards containing large numbers of items, this can result in a significant performance improvement. Initial period selection within Data Browser and reports. The User Preferences facility has been extended to allow you to specify the initial period selection when first entering the Data Browser or reports facility. The default is the last hour. Performance improvement when querying the all sessions group. Technical Prerequisites, Download and Installation Instructions The Linux version of the plug-in is available for immediate download from Oracle Technology Network or Oracle eDelivery. For specific information regarding technical prerequisites, product download and installation, please refer to My Oracle Support note 1224313.1. The following certifications are in progress: * Oracle Solaris on SPARC (64-bit) (9, 10) * HP-UX Itanium (11.23, 11.31) * HP-UX PA-RISC (64-bit) (11.23, 11.31) * IBM AIX on Power Systems (64-bit) (5.3, 6.1)

  Read the article

• Interesting links week #24 and #25

  - by erwin21

  Below a list of interesting links that I found this week: Interaction: Design Usability and All About It Frontend: CSS Lint – CSS Cleaning Tool 10 HTML Entity Crimes You Really Shouldn’t Commit Development: OWASP Top 10 for .NET developers part 7: Insecure Cryptographic Storage C#/.NET Fundamentals: Choosing the Right Collection Class Mobile: Tips to Design a Website for Mobile Marketing: 30 (New) Google Ranking Factors You May Over- or Underestimate Other: 5 Little-Known Web Files That Can Enhance Your Website Interested in more interesting links follow me at twitter http://twitter.com/erwingriekspoor

  Read the article

• We are hiring (take a minute to read this, is not another BS talk ;) )

  - by gsusx

  I really wanted to wait until our new website was out to blog about this but I hope you can put up with the ugly website for a few more days J. Tellago keeps growing and, after a quick break at the beginning of the year, we are back in hiring mode J. We are currently expanding our teams in the United States and Argentina and have various positions open in the following categories. .NET developers: If you are an exceptional .NET programmer with a passion for creating great software solutions working...(read more)

  Read the article

• AWStats: Visits from IP address vs Crawlers

  - by user3651934

  I use AWStats in cPanel to see stats of my website. Under Hosts section I see one IP address that has visited 150 pages. I am not sure if one person would have visited 150 pages using a browser. But if these 150 pages have been visited using a software application, then should not it be listed under Robots/Spider section. So how do I determine if I should block a certain IP address that has visited several hundred pages of my website? Thanks

  Read the article

• Cloud Based Load Testing Using TF Service &amp; VS 2013

  - by Tarun Arora [Microsoft MVP]

  Originally posted on: http://geekswithblogs.net/TarunArora/archive/2013/06/30/cloud-based-load-testing-using-tf-service-amp-vs-2013.aspx One of the new features announced as part of the Visual Studio 2013 Ultimate Preview is ‘Cloud Based Load Testing’. In this blog post I’ll walk you through, What is Cloud Based Load Testing? How have I been using this feature? – Success story! Where can you find more resources on this feature? What is Cloud Based Load Testing? It goes without saying that performance testing your application not only gives you the confidence that the application will work under heavy levels of stress but also gives you the ability to test how scalable the architecture of your application is. It is important to know how much is too much for your application! Working with various clients in the industry I have realized that the biggest barriers in Load Testing & Performance Testing adoption are, High infrastructure and administration cost that comes with this phase of testing Time taken to procure & set up the test infrastructure Finding use for this infrastructure investment after completion of testing Is cloud the answer? 100% Visual Studio Compatible Scalable and Realistic Start testing in < 2 minutes Intuitive Pay only for what you need Use existing on premise tests on cloud There are a lot of vendors out there offering Cloud Based Load Testing, to name a few, Load Storm Soasta Blaze Meter Blitz And others… The question you may want to ask is, why should you go with Microsoft’s Cloud based Load Test offering. If you are a Microsoft shop or already have investments in Microsoft technologies, you’ll see great benefit in the natural integration this offers with existing Microsoft products such as Visual Studio and Windows Azure. For example, your existing Web tests authored in Visual Studio 2010 or Visual Studio 2012 will run on the cloud without requiring any modifications what so ever. Microsoft’s cloud test rig also supports API based testing, for example, if you are building a WPF application which consumes WCF services, you can write unit tests to invoke the WCF service, these tests can be run on the cloud test rig and loaded with ‘N’ concurrent users for performance testing. If you have your assets already hosted in the Azure and possibly in the same data centre as the Cloud test rig, your Azure app will not incur a usage cost because of the generated traffic since the traffic is coming from the same data centre. The licensing or pricing information on Microsoft’s cloud based Load test service is yet to be announced, but I would expect this to be priced attractively to match the market competition.   The only additional configuration required for running load tests on Microsoft Cloud based Load Tests service is to select the Test run location as Run tests using Visual Studio Team Foundation Service, How have I been using Microsoft’s Cloud based Load Test Service? I have been part of the Microsoft Cloud Based Load Test Service advisory council for the last 7 months. This gave the opportunity to see the product shape up from concept to working solution. I was also the first person outside of Microsoft to try this offering out. This gave me the opportunity to test real world application at various clients using the Microsoft Load Test Service and provide real world feedback to the Microsoft product team. One of the most recent systems I tested using the Load Test Service has been an insurance quote generation engine. This insurance quote generation engine is,   hosted in Windows Azure expected to get quote requests from across the globe expected to handle 5 Million quote requests in a day (not clear how this load will be distributed across the day) There was no way, I could simulate such kind of load from on premise without standing up additional hardware. But Microsoft’s Cloud based Load Test service allowed me to test my key performance testing scenarios, i.e. Simulate expected Load, Endurance Testing, Threshold Testing and Testing for Latency. Simulating expected load: approach to devising a load pattern My approach to devising a load test pattern has been to run the test scenario with 1 user to figure out the response time. Then work out how many users are required to reach the target load. So, for example, to invoke 1 quote from the quote engine software takes 0.5 seconds. Now if you do the math,   1 quote request by 1 user = 0.5 seconds   quotes generated by 1 user in 24 hour = 1 * (((2 * 60) * 60) * 24) = 172,800   quotes generated by 30 users in 24 hours = 172,800 * 30 =  5,184,000 This was a very simple example, if your application requires more concurrent users to test scenario’s such as caching, etc then you can devise your own load pattern, some examples of load test patterns can be found here.  Endurance Testing To test for endurance, I loaded the quote generation engine with an expected fixed user load and ran the test for very long duration such as over 48 hours and observed the affect of the long running test on the Azure infrastructure. Currently Microsoft Load Test service does not support metrics from the machine under test. I used Azure diagnostics to begin with, but later started using Cerebrata Azure Diagnostics Manager to capture the metrics of the machine under test. Threshold Testing To figure out how much user load the application could cope with before falling on its belly, I opted to step load the quote generation engine by incrementing user load with different variations of incremental user load per minute till the application crashed out and forced an IIS reset. Testing for Latency Currently the Microsoft Load Test service does not support generating geographically distributed load, I however, deployed the insurance quote generation engine in different Azure data centres and ran the same set of performance tests to measure for latency. Because I could compare load test results from different runs by exporting the results to excel (this feature is provided out of the box right from Visual Studio 2010) I could see the different in response times. More resources on Microsoft Cloud based Load Test Service A few important links to get you started, Download Visual Studio Ultimate 2013 Preview Getting started guide for load testing using Team Foundation Service Troubleshooting guide for FAQs and known issues Team Foundation Service forum for questions and support Detailed demo and presentation (link to Tech-Ed session recording) Detailed demo and presentation (link to Build session recording) There a few limits on the usage of Microsoft Cloud based Load Test service that you can read about here. If you have any feedback on Microsoft Cloud based Load Test service, feel free to share it with the product team via the Visual Studio User Voice forum. I hope you found this useful. Thank you for taking the time out and reading this blog post. If you enjoyed the post, remember to subscribe to http://feeds.feedburner.com/TarunArora. Stay tuned!

  Read the article

• Search Engine Optimization - The Importance of Page Optimization in Search Engine Optimization

  In order for your website to rank well, your internal linking structure is critical to your success. This is covered some of the theory for this in various articles and blogs about Page Structure of a website, which said how you should map out the physical linking structure, but in this guide I will explain more about the importance of interlinking your pages, while using your targeted keyword in your anchor text.

  Read the article

• SEO - Articles Are the Way Forward

  Writing articles for websites is different from other forms of writing because it uses SEO keywords, designed to improve your site and achieve higher rankings within the search engine. This type of writing is often referred to as copy writing or writing content. Writing articles for websites is one of the most effective marketing methods for a website and they are often used to promote the use of keywords and diverting traffic to a website.

  Read the article

• Why Use Google Webmaster Tools

  This article talks about why Google Webmaster Tools is an amazing program for optimizing and debugging your website. It provides many advantages for any website owner who uses it.

  Read the article

• Integrating Flickr with ASP.Net application

  - by sreejukg

  Flickr is the popular photo management and sharing application offered by yahoo. The services from flicker allow you to store and share photos and videos online. Flicker offers strong API support for almost all services they provide. Using this API, developers can integrate photos to their public website. Since 2005, developers have collaborated on top of Flickr's APIs to build fun, creative, and gorgeous experiences around photos that extend beyond Flickr. In this article I am going to demonstrate how easily you can bring the photos stored on flicker to your website. Let me explain the scenario this article is trying to address. I have a flicker account where I upload photos and share in many ways offered by Flickr. Now I have a public website, instead of re-upload the photos again to public website, I want to show this from Flickr. Also I need complete control over what photo to display. So I went and referred the Flickr documentation and there is API support ready to address my scenario (and more… ). FlickerAPI for ASP.Net To Integrate Flicker with ASP.Net applications, there is a library available in CodePlex. You can find it here http://flickrnet.codeplex.com/ Visit the URL and download the latest version. The download includes a Zip file, when you unzip you will get a number of dlls. Since I am going to use ASP.Net application, I need FlickrNet.dll. See the screenshot of all the dlls, and there is a help file available in the download (.chm) for your reference. Once you have the dll, you need to use Flickr API from your website. I assume you have a flicker account and you are familiar with Flicker services. Arrange your photos using Sets in Flickr In flicker, you can define sets and add your uploaded photos to sets. You can compare set to photo album. A set is a logical collection of photos, which is an excellent option for you to categorize your photos. Typically you will have a number of sets each set having few photos. You can write application that brings photos from sets to your website. For the purpose of this article I already created a set Flickr and added some photos to it. Once you logged in to Flickr, you can see the Sets under the Menu. In the Sets page, you will see all the sets you have created. As you notice, you can see certain sample images I have uploaded just to test the functionality. Though I wish I couldn’t create good photos so please bear with me. I have created 2 photo sets named Blue Album and Red Album. Click on the image for the set, will take you to the corresponding set page. In the set “Red Album” there are 4 photos and the set has a unique ID (highlighted in the URL). You can simply retrieve the photos with the set id from your application. In this article I am going to retrieve the images from Red album in my ASP.Net page. For that First I need to setup FlickrAPI for my usage. Configure Flickr API Key As I mentioned, we are going to use Flickr API to retrieve the photos stored in Flickr. In order to get access to Flickr API, you need an API key. To create an API key, navigate to the URL http://www.flickr.com/services/apps/create/ Click on Request an API key link, now you need to tell Flickr whether your application in commercial or non-commercial. I have selected a non-commercial key. Now you need to enter certain information about your application. Once you enter the details, Click on the submit button. Now Flickr will create the API key for your application. Generating non-commercial API key is very easy, in couple of steps the key will be generated and you can use the key in your application immediately. ASP.Net application for retrieving photos Now we need write an ASP.Net application that display pictures from Flickr. Create an empty web application (I named this as FlickerIntegration) and add a reference to FlickerNet.dll. Add a web form page to the application where you will retrieve and display photos(I have named this as Gallery.aspx). After doing all these, the solution explorer will look similar to following. I have used the below code in the Gallery.aspx page. The output for the above code is as follows. I am going to explain the code line by line here. First it is adding a reference to the FlickrNet namespace. using FlickrNet; Then create a Flickr object by using your API key. Flickr f = new Flickr("<yourAPIKey>"); Now when you retrieve photos, you can decide what all fields you need to retrieve from Flickr. Every photo in Flickr contains lots of information. Retrieving all will affect the performance. For the demonstration purpose, I have retrieved all the available fields as follows. PhotoSearchExtras.All But if you want to specify the fields you can use logical OR operator(|). For e.g. the following statement will retrieve owner name and date taken. PhotoSearchExtras extraInfo = PhotoSearchExtras.OwnerName | PhotoSearchExtras.DateTaken; Then retrieve all the photos from a photo set using PhotoSetsGetPhotos method. I have passed the PhotoSearchExtras object created earlier. PhotosetPhotoCollection photos = f.PhotosetsGetPhotos("72157629872940852", extraInfo); The PhotoSetsGetPhotos method will return a collection of Photo objects. You can just navigate through the collection using a foreach statement. foreach (Photo p in photos) {     //access each photo properties } Photo class have lot of properties that map with the properties from Flickr. The chm documentation comes along with the CodePlex download is a great asset for you to understand the fields. In the above code I just used the following p.LargeUrl – retrieves the large image url for the photo. p.ThumbnailUrl – retrieves the thumbnail url for the photo p.Title – retrieves the Title of the photo p.DateUploaded – retrieves the date of upload Visual Studio intellisense will give you all properties, so it is easy, you can just try with Visual Studio intellisense to find the right properties you are looking for. Most of hem are self-explanatory. So you can try retrieving the required properties. In the above code, I just pushed the photos to the page. In real time you can use the retrieved photos along with JQuery libraries to create animated photo galleries, slideshows etc. Configuration and Troubleshooting If you get access denied error while executing the code, you need to disable the caching in Flickr API. FlickrNet cache the photos to your local disk when retrieved. You can specify a cache folder where the application need write permission. You can specify the Cache folder in the code as follows. Flickr.CacheLocation = Server.MapPath("./FlickerCache/"); If the application doesn’t have have write permission to the cache folder, the application will throw access denied error. If you cannot give write permission to the cache folder, then you must disable the caching. You can do this from code as follows. Flickr.CacheDisabled = true; Disabling cache will have an impact on the performance. Take care! Also you can define the Flickr settings in web.config file.You can find the documentation here. http://flickrnet.codeplex.com/wikipage?title=ExampleConfigFile&ProjectName=flickrnet Flickr is a great place for storing and sharing photos. The API access allows developers to do seamless integration with the photos uploaded on Flickr.

  Read the article

• How to Recruit a Web Firm in India for Your Success Business

  There are certain parameters that have to be taken into account while recruiting a web firm. The right web firm will put your website on the path to success where as an inappropriate website would ce... [Author: John Anthony - Computers and Internet - June 04, 2010]

  Read the article

• Solaris X86 AESNI OpenSSL Engine

  - by danx

  Solaris X86 AESNI OpenSSL Engine Cryptography is a major component of secure e-commerce. Since cryptography is compute intensive and adds a significant load to applications, such as SSL web servers (https), crypto performance is an important factor. Providing accelerated crypto hardware greatly helps these applications and will help lead to a wider adoption of cryptography, and lower cost, in e-commerce and other applications. The Intel Westmere microprocessor has six new instructions to acclerate AES encryption. They are called "AESNI" for "AES New Instructions". These are unprivileged instructions, so no "root", other elevated access, or context switch is required to execute these instructions. These instructions are used in a new built-in OpenSSL 1.0 engine available in Solaris 11, the aesni engine. Previous Work Previously, AESNI instructions were introduced into the Solaris x86 kernel and libraries. That is, the "aes" kernel module (used by IPsec and other kernel modules) and the Solaris pkcs11 library (for user applications). These are available in Solaris 10 10/09 (update 8) and above, and Solaris 11. The work here is to add the aesni engine to OpenSSL. X86 AESNI Instructions Intel's Xeon 5600 is one of the processors that support AESNI. This processor is used in the Sun Fire X4170 M2 As mentioned above, six new instructions acclerate AES encryption in processor silicon. The new instructions are: aesenc performs one round of AES encryption. One encryption round is composed of these steps: substitute bytes, shift rows, mix columns, and xor the round key. aesenclast performs the final encryption round, which is the same as above, except omitting the mix columns (which is only needed for the next encryption round). aesdec performs one round of AES decryption aesdeclast performs the final AES decryption round aeskeygenassist Helps expand the user-provided key into a "key schedule" of keys, one per round aesimc performs an "inverse mixed columns" operation to convert the encryption key schedule into a decryption key schedule pclmulqdq Not a AESNI instruction, but performs "carryless multiply" operations to acclerate AES GCM mode. Since the AESNI instructions are implemented in hardware, they take a constant number of cycles and are not vulnerable to side-channel timing attacks that attempt to discern some bits of data from the time taken to encrypt or decrypt the data. Solaris x86 and OpenSSL Software Optimizations Having X86 AESNI hardware crypto instructions is all well and good, but how do we access it? The software is available with Solaris 11 and is used automatically if you are running Solaris x86 on a AESNI-capable processor. AESNI is used internally in the kernel through kernel crypto modules and is available in user space through the PKCS#11 library. For OpenSSL on Solaris 11, AESNI crypto is available directly with a new built-in OpenSSL 1.0 engine, called the "aesni engine." This is in lieu of the extra overhead of going through the Solaris OpenSSL pkcs11 engine, which accesses Solaris crypto and digest operations. Instead, AESNI assembly is included directly in the new aesni engine. Instead of including the aesni engine in a separate library in /lib/openssl/engines/, the aesni engine is "built-in", meaning it is included directly in OpenSSL's libcrypto.so.1.0.0 library. This reduces overhead and the need to manually specify the aesni engine. Since the engine is built-in (that is, in libcrypto.so.1.0.0), the openssl -engine command line flag or API call is not needed to access the engine—the aesni engine is used automatically on AESNI hardware. Ciphers and Digests supported by OpenSSL aesni engine The Openssl aesni engine auto-detects if it's running on AESNI hardware and uses AESNI encryption instructions for these ciphers: AES-128-CBC, AES-192-CBC, AES-256-CBC, AES-128-CFB128, AES-192-CFB128, AES-256-CFB128, AES-128-CTR, AES-192-CTR, AES-256-CTR, AES-128-ECB, AES-192-ECB, AES-256-ECB, AES-128-OFB, AES-192-OFB, and AES-256-OFB. Implementation of the OpenSSL aesni engine The AESNI assembly language routines are not a part of the regular Openssl 1.0.0 release. AESNI is a part of the "HEAD" ("development" or "unstable") branch of OpenSSL, for future release. But AESNI is also available as a separate patch provided by Intel to the OpenSSL project for OpenSSL 1.0.0. A minimal amount of "glue" code in the aesni engine works between the OpenSSL libcrypto.so.1.0.0 library and the assembly functions. The aesni engine code is separate from the base OpenSSL code and requires patching only a few source files to use it. That means OpenSSL can be more easily updated to future versions without losing the performance from the built-in aesni engine. OpenSSL aesni engine Performance Here's some graphs of aesni engine performance I measured by running openssl speed -evp $algorithm where $algorithm is aes-128-cbc, aes-192-cbc, and aes-256-cbc. These are using the 64-bit version of openssl on the same AESNI hardware, a Sun Fire X4170 M2 with a Intel Xeon E5620 @2.40GHz, running Solaris 11 FCS. "Before" is openssl without the aesni engine and "after" is openssl with the aesni engine. The numbers are MBytes/second. OpenSSL aesni engine performance on Sun Fire X4170 M2 (Xeon E5620 @2.40GHz) (Higher is better; "before"=OpenSSL on AESNI without AESNI engine software, "after"=OpenSSL AESNI engine) As you can see the speedup is dramatic for all 3 key lengths and for data sizes from 16 bytes to 8 Kbytes—AESNI is about 7.5-8x faster over hand-coded amd64 assembly (without aesni instructions). Verifying the OpenSSL aesni engine is present The easiest way to determine if you are running the aesni engine is to type "openssl engine" on the command line. No configuration, API, or command line options are needed to use the OpenSSL aesni engine. If you are running on Intel AESNI hardware with Solaris 11 FCS, you'll see this output indicating you are using the aesni engine: intel-westmere $ openssl engine (aesni) Intel AES-NI engine (no-aesni) (dynamic) Dynamic engine loading support (pkcs11) PKCS #11 engine support If you are running on Intel without AESNI hardware you'll see this output indicating the hardware can't support the aesni engine: intel-nehalem $ openssl engine (aesni) Intel AES-NI engine (no-aesni) (dynamic) Dynamic engine loading support (pkcs11) PKCS #11 engine support For Solaris on SPARC or older Solaris OpenSSL software, you won't see any aesni engine line at all. Third-party OpenSSL software (built yourself or from outside Oracle) will not have the aesni engine either. Solaris 11 FCS comes with OpenSSL version 1.0.0e. The output of typing "openssl version" should be "OpenSSL 1.0.0e 6 Sep 2011". 64- and 32-bit OpenSSL OpenSSL comes in both 32- and 64-bit binaries. 64-bit executable is now the default, at /usr/bin/openssl, and OpenSSL 64-bit libraries at /lib/amd64/libcrypto.so.1.0.0 and libssl.so.1.0.0 The 32-bit executable is at /usr/bin/i86/openssl and the libraries are at /lib/libcrytpo.so.1.0.0 and libssl.so.1.0.0. Availability The OpenSSL AESNI engine is available in Solaris 11 x86 for both the 64- and 32-bit versions of OpenSSL. It is not available with Solaris 10. You must have a processor that supports AESNI instructions, otherwise OpenSSL will fallback to the older, slower AES implementation without AESNI. Processors that support AESNI include most Westmere and Sandy Bridge class processor architectures. Some low-end processors (such as for mobile/laptop platforms) do not support AESNI. The easiest way to determine if the processor supports AESNI is with the isainfo -v command—look for "amd64" and "aes" in the output: $ isainfo -v 64-bit amd64 applications pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu Conclusion The Solaris 11 OpenSSL aesni engine provides easy access to powerful Intel AESNI hardware cryptography, in addition to Solaris userland PKCS#11 libraries and Solaris crypto kernel modules.

  Read the article

• Show "results - of" of internal search in Google search result

  - by Petra Barus

  I was doing some searches on Google Search and I stumbled on this As you can see in the screenshot above, the search results show a summary of an internal search page (the one I highlighted by red underline) on the website (homes.com and findaproperty.com). I would like to show up this kind of result in the Google search for my website internal search. How do I do it? Do I have to put some metatag or something?

  Read the article

< Previous Page | 371 372 373 374 375 376 377 378 379 380 381 382  | Next Page >