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App Store: Profitability for Game Developers

- by Bunkai.Satori

Recent days, I've been spending significant time in discovering chances of profitability of AppStore for developers. I have found many articles. Some of them are highly optimistic, while other are extremely skeptical. This article is extremely skeptical. It even claims to have backed its conclusions by objective sales numbers. This is another pesimistic article saying that games developed by single individuals get 20 downloads a day. Can I kindly ask to clarify from business viewpoint whether average developers publishing games and software on AppStore can cover their living expenses, even, whether they can become profitable? Is it achievable to generate revenues of 50.000 USD yearly on AppStore for a single developer? I would like to stay as realistic as possible. Despite the question might look subjective, a good business man will be able to esitmate chances for profitability and prosperity within AppStore.

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App Store: Profitability for Game Developers

- by Bunkai.Satori

Recent days, I've been spending significant time in discovering chances of profitability of AppStore for developers. I have found many articles. Some of them are highly optimistic, while other are extremely skeptical. This article is extremely skeptical. It even claims to have backed its conclusions by objective sales numbers. This is another pesimistic article saying that games developed by single individuals get 20 downloads a day. Can I kindly ask to clarify from business viewpoint whether average developers publishing games and software on AppStore can cover their living expenses, even, whether they can become profitable? Is it achievable to generate revenues of 50.000 USD yearly on AppStore for a single developer? I would like to stay as realistic as possible. Despite the question might look subjective, a good business man will be able to esitmate chances for profitability and prosperity within AppStore.

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Dynamic Memory Allocation and Memory Management

- by Bunkai.Satori

In an average game, there are hundreds or maybe thousands of objects in the scene. Is it completely correct to allocate memory for all objects, including gun shots (bullets), dynamically via default new()? Should I create any memory pool for dynamic allocation, or is there no need to bother with this? What if the target platform are mobile devices? Is there a need for a memory manager in a mobile game, please? Thank you. Language Used: C++; Currently developed under Windows, but planned to be ported later.

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Autoscaling in a modern world…. Part 2

- by Steve Loethen

When we last left off, we had a web application spinning away in the cloud, and a local console application watching it and reacting to changes in demand. Reactions that were specified by a set of rules. Let’s talk about those rules. Constraints. The first set of rules this application answered to were the constraints. Here is what they looked like: <constraintRules> <rule name="default" enabled="true" rank="1" description="The default constraint rule"> <actions> <range min="1" max="4" target="AutoscalingApplicationRole"/> </actions> </rule> </constraintRules> Pretty basic. We have one role, the “AutoscalingApplicationRole”, and we have decided to have it live within a range of 1 to 4. This rule does not adjust, but instead, set’s limits on what other rules can do. It has a rank, so you can have you can specify other sets of constraints, perhaps based on time or date, to allow for deviations from this set. But for now, let’s keep it simple. In the real world, you would probably use the minimum to set a lower end SLA. A common value might be a 2, to prevent the reactive rules from ever taking you down to 1 role. The maximum is often used to keep a rule from driving the cost up, setting an upper limit to prevent you waking up one morning and find a bill for hundreds of instances you didn’t expect. So, here we have the range we want our application to live inside. This is good for our investigation and testing. Next, let’s take a look at the reactive rules. These rules are what you use to react (hence reactive rules) to changing demands on your application. The HOL has two simple rules. One that looks at a queue depth, and one that looks at a performance counter that reports cpu utilization. the XML in the rules file looks like this: <reactiveRules> <rule name="ScaleUp" rank="10" description="Scale Up the web role" enabled="true"> <when> <any> <greaterOrEqual operand="Length_05_holqueue" than="10"/> <greaterOrEqual operand="CPU_05_holwebrole" than="65"/> </any> </when> <actions> <scale target="AutoscalingApplicationRole" by="1"/> </actions> </rule> <rule name="ScaleDown" rank="10" description="Scale down the web role" enabled="true"> <when> <all> <less operand="Length_05_holqueue" than="5"/> <less operand="CPU_05_holwebrole" than="40"/> </all> </when> <actions> <scale target="AutoscalingApplicationRole" by="-1"/> </actions> </rule> </reactiveRules> <operands> <performanceCounter alias="CPU_05_holwebrole" performanceCounterName="\Processor(_Total)\% Processor Time" source="AutoscalingApplicationRole" timespan="00:05:00" aggregate="Average" /> <queueLength alias="Length_05_holqueue" queue="hol-queue" timespan="00:05:00" aggregate="Average"/> </operands> These rules are currently contained in a file called rules.xml, that is in the root of the console application. The console app, starts up, grabs the rules and starts watching the 2 operands. When it detects a rule has been satisfied, it performs the desired action. (here, scale up or down my 1). But I want to host the autoscaler in the cloud. For my first trick, I will move the rules (and another file called services.xml) to azure blob storage. Look for part 3.

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Web Application Tasks Estimation

- by Ali

I know the answer depends on the exact project and its requirements but i am asking on the avarage % of the total time goes into the tasks of the web application development statistically from your own experiance. While developing a web application (database driven) How much % of time does each of the following activities usually takes: -- database creation & all related stored procedures -- server side development -- client side development -- layout settings and designing I know there are lots of great web application developers around here and each one of you have done fair amount of web development and as a result there could be an almost fixed percentage of time going to each of the above activities of web developments for standard projects Update : I am not expecting someone to tell me number of hours i am asking about the average percentage of time that goes on each of the activities as per your experience i.e. server side dev 50%, client side development 20% ,,,,, I repeat there will be lots of cases that differs from the standard depending on the exact requirments of each web application project but here i am asking about Avarage for standard (no special requirment) web project

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Wow Twitter!!! Ten billions and counting

- by samsudeen

Twitter the micro blogging site crossed the ten billions milestone on 4th of this month as per the report by GigaTweet (Site which tracks the number of tweets posted on twitter) The person who sent the 10 billionth tweet is still unknown as his profile is protected. But the 9,999,999,999th tweet was sent by one Rafaela Marques from Brazil. AS you can see GigaTweet expects just another 196 days to reach the 20 billionth marks if tweet continues with the current pace. Some of the interesting statics about rate in which people tweeted every year 2007 – 5000 tweets per day 2008 – 300,000 tweets per day 2009 – 2.5 million per day It reached an average of 35 million tweets per day by end 2009. Today believe it or not the tweet rate is 50 million tweets per day and that’s why we call Wow Twitter!!! . Join us on Facebook to read all our stories right inside your Facebook news feed.

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Composite Moon Map Offers Stunning Views of the Lunar Surface [Astronomy]

- by Jason Fitzpatrick

Researchers at Arizona State University have stitched together a massive high-resolution map of the moon; seen the moon in astounding detail. Using images fro the Lunar Reconnaissance Orbiter (LRO) they carefully stitch a massive map of the moon with a higher resolution than the public has ever seen before: The WAC has a pixel scale of about 75 meters, and with an average altitude of 50 km, a WAC image swath is 70 km wide across the ground-track. Because the equatorial distance between orbits is about 30 km, there is nearly complete orbit-to-orbit stereo overlap all the way around the Moon, every month. Using digital photogrammetric techniques, a terrain model was computed from this stereo overlap. Hit up the link below to check out the images and the process they used. Lunar Topography as Never Seen Before [via NASA] How to Make the Kindle Fire Silk Browser *Actually* Fast! Amazon’s New Kindle Fire Tablet: the How-To Geek Review HTG Explains: How Hackers Take Over Web Sites with SQL Injection / DDoS

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The Unspoken - The Why of GC Ergonomics

- by jonthecollector

Do you use GC ergonomics, -XX:+UseAdaptiveSizePolicy, with the UseParallelGC collector? The jist of GC ergonomics for that collector is that it tries to grow or shrink the heap to meet a specified goal. The goals that you can choose are maximum pause time and/or throughput. Don't get too excited there. I'm speaking about UseParallelGC (the throughput collector) so there are definite limits to what pause goals can be achieved. When you say out loud "I don't care about pause times, give me the best throughput I can get" and then say to yourself "Well, maybe 10 seconds really is too long", then think about a pause time goal. By default there is no pause time goal and the throughput goal is high (98% of the time doing application work and 2% of the time doing GC work). You can get more details on this in my very first blog. GC ergonomics The UseG1GC has its own version of GC ergonomics, but I'll be talking only about the UseParallelGC version. If you use this option and wanted to know what it (GC ergonomics) was thinking, try -XX:AdaptiveSizePolicyOutputInterval=1 This will print out information every i-th GC (above i is 1) about what the GC ergonomics to trying to do. For example, UseAdaptiveSizePolicy actions to meet *** throughput goal *** GC overhead (%) Young generation: 16.10 (attempted to grow) Tenured generation: 4.67 (attempted to grow) Tenuring threshold: (attempted to decrease to balance GC costs) = 1 GC ergonomics tries to meet (in order) Pause time goal Throughput goal Minimum footprint The first line says that it's trying to meet the throughput goal. UseAdaptiveSizePolicy actions to meet *** throughput goal *** This run has the default pause time goal (i.e., no pause time goal) so it is trying to reach a 98% throughput. The lines Young generation: 16.10 (attempted to grow) Tenured generation: 4.67 (attempted to grow) say that we're currently spending about 16% of the time doing young GC's and about 5% of the time doing full GC's. These percentages are a decaying, weighted average (earlier contributions to the average are given less weight). The source code is available as part of the OpenJDK so you can take a look at it if you want the exact definition. GC ergonomics is trying to increase the throughput by growing the heap (so says the "attempted to grow"). The last line Tenuring threshold: (attempted to decrease to balance GC costs) = 1 says that the ergonomics is trying to balance the GC times between young GC's and full GC's by decreasing the tenuring threshold. During a young collection the younger objects are copied to the survivor spaces while the older objects are copied to the tenured generation. Younger and older are defined by the tenuring threshold. If the tenuring threshold hold is 4, an object that has survived fewer than 4 young collections (and has remained in the young generation by being copied to the part of the young generation called a survivor space) it is younger and copied again to a survivor space. If it has survived 4 or more young collections, it is older and gets copied to the tenured generation. A lower tenuring threshold moves objects more eagerly to the tenured generation and, conversely a higher tenuring threshold keeps copying objects between survivor spaces longer. The tenuring threshold varies dynamically with the UseParallelGC collector. That is different than our other collectors which have a static tenuring threshold. GC ergonomics tries to balance the amount of work done by the young GC's and the full GC's by varying the tenuring threshold. Want more work done in the young GC's? Keep objects longer in the survivor spaces by increasing the tenuring threshold. This is an example of the output when GC ergonomics is trying to achieve a pause time goal UseAdaptiveSizePolicy actions to meet *** pause time goal *** GC overhead (%) Young generation: 20.74 (no change) Tenured generation: 31.70 (attempted to shrink) The pause goal was set at 50 millisecs and the last GC was 0.415: [Full GC (Ergonomics) [PSYoungGen: 2048K-0K(26624K)] [ParOldGen: 26095K-9711K(28992K)] 28143K-9711K(55616K), [Metaspace: 1719K-1719K(2473K/6528K)], 0.0758940 secs] [Times: user=0.28 sys=0.00, real=0.08 secs] The full collection took about 76 millisecs so GC ergonomics wants to shrink the tenured generation to reduce that pause time. The previous young GC was 0.346: [GC (Allocation Failure) [PSYoungGen: 26624K-2048K(26624K)] 40547K-22223K(56768K), 0.0136501 secs] [Times: user=0.06 sys=0.00, real=0.02 secs] so the pause time there was about 14 millisecs so no changes are needed. If trying to meet a pause time goal, the generations are typically shrunk. With a pause time goal in play, watch the GC overhead numbers and you will usually see the cost of setting a pause time goal (i.e., throughput goes down). If the pause goal is too low, you won't achieve your pause time goal and you will spend all your time doing GC. GC ergonomics is meant to be simple because it is meant to be used by anyone. It was not meant to be mysterious and so this output was added. If you don't like what GC ergonomics is doing, you can turn it off with -XX:-UseAdaptiveSizePolicy, but be pre-warned that you have to manage the size of the generations explicitly. If UseAdaptiveSizePolicy is turned off, the heap does not grow. The size of the heap (and the generations) at the start of execution is always the size of the heap. I don't like that and tried to fix it once (with some help from an OpenJDK contributor) but it unfortunately never made it out the door. I still have hope though. Just a side note. With the default throughput goal of 98% the heap often grows to it's maximum value and stays there. Definitely reduce the throughput goal if footprint is important. Start with -XX:GCTimeRatio=4 for a more modest throughput goal (%20 of the time spent in GC). A higher value means a smaller amount of time in GC (as the throughput goal).

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Alcatel-Lucent Boosts Broadband Over Copper To 300Mbps

- by Ratman21

alphadogg at Slashdot writes "Alcatel-Lucent has come up with a way to [0]move data at 300Mbps over copper lines. So far the results have only been reproduced in a lab environment â€” real products and services won't be available for at least a year. From the article: 'Researchers at the company's Bell Labs demonstrated the 300Mbps technology over a distance of 400 meters using VDSL2 (Very high bitrate Digital Subscriber Line), according to Stefaan Vanhastel, director of product marketing at Alcatel-Lucent Wireline Networks. The test showed that it can also do 100Mbps over a distance of 1,000 meters, he said. Currently, copper is the most common broadband medium. About 65 percent of subscribers have a broadband connection that's based on DSL, compared to 20 percent for cable and 12 percent for fiber, according to market research company Point Topic. Today, the average advertised DSL speeds for residential users vary between 9.2 Mbps and 1.9Mbps in various parts of the world, Point Topic said.'" Discuss this story at: http://tech.slashdot.org/comments.pl?sid=10/04/21/239243

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SPARC T4-4 Delivers World Record First Result on PeopleSoft Combined Benchmark

- by Brian

Oracle's SPARC T4-4 servers running Oracle's PeopleSoft HCM 9.1 combined online and batch benchmark achieved World Record 18,000 concurrent users while executing a PeopleSoft Payroll batch job of 500,000 employees in 43.32 minutes and maintaining online users response time at < 2 seconds. This world record is the first to run online and batch workloads concurrently. This result was obtained with a SPARC T4-4 server running Oracle Database 11g Release 2, a SPARC T4-4 server running PeopleSoft HCM 9.1 application server and a SPARC T4-2 server running Oracle WebLogic Server in the web tier. The SPARC T4-4 server running the application tier used Oracle Solaris Zones which provide a flexible, scalable and manageable virtualization environment. The average CPU utilization on the SPARC T4-2 server in the web tier was 17%, on the SPARC T4-4 server in the application tier it was 59%, and on the SPARC T4-4 server in the database tier was 35% (online and batch) leaving significant headroom for additional processing across the three tiers. The SPARC T4-4 server used for the database tier hosted Oracle Database 11g Release 2 using Oracle Automatic Storage Management (ASM) for database files management with I/O performance equivalent to raw devices. This is the first three tier mixed workload (online and batch) PeopleSoft benchmark also processing PeopleSoft payroll batch workload. Performance Landscape PeopleSoft HR Self-Service and Payroll Benchmark Systems Users Ave Response Search (sec) Ave Response Save (sec) Batch Time (min) Streams SPARC T4-2 (web) SPARC T4-4 (app) SPARC T4-2 (db) 18,000 0.944 0.503 43.32 64 Configuration Summary Application Configuration: 1 x SPARC T4-4 server with 4 x SPARC T4 processors, 3.0 GHz 512 GB memory 5 x 300 GB SAS internal disks 1 x 100 GB and 2 x 300 GB internal SSDs 2 x 10 Gbe HBA Oracle Solaris 11 11/11 PeopleTools 8.52 PeopleSoft HCM 9.1 Oracle Tuxedo, Version 10.3.0.0, 64-bit, Patch Level 031 Java Platform, Standard Edition Development Kit 6 Update 32 Database Configuration: 1 x SPARC T4-4 server with 4 x SPARC T4 processors, 3.0 GHz 256 GB memory 3 x 300 GB SAS internal disks Oracle Solaris 11 11/11 Oracle Database 11g Release 2 Web Tier Configuration: 1 x SPARC T4-2 server with 2 x SPARC T4 processors, 2.85 GHz 256 GB memory 2 x 300 GB SAS internal disks 1 x 100 GB internal SSD Oracle Solaris 11 11/11 PeopleTools 8.52 Oracle WebLogic Server 10.3.4 Java Platform, Standard Edition Development Kit 6 Update 32 Storage Configuration: 1 x Sun Server X2-4 as a COMSTAR head for data 4 x Intel Xeon X7550, 2.0 GHz 128 GB memory 1 x Sun Storage F5100 Flash Array (80 flash modules) 1 x Sun Storage F5100 Flash Array (40 flash modules) 1 x Sun Fire X4275 as a COMSTAR head for redo logs 12 x 2 TB SAS disks with Niwot Raid controller Benchmark Description This benchmark combines PeopleSoft HCM 9.1 HR Self Service online and PeopleSoft Payroll batch workloads to run on a unified database deployed on Oracle Database 11g Release 2. The PeopleSoft HRSS benchmark kit is a Oracle standard benchmark kit run by all platform vendors to measure the performance. It's an OLTP benchmark where DB SQLs are moderately complex. The results are certified by Oracle and a white paper is published. PeopleSoft HR SS defines a business transaction as a series of HTML pages that guide a user through a particular scenario. Users are defined as corporate Employees, Managers and HR administrators. The benchmark consist of 14 scenarios which emulate users performing typical HCM transactions such as viewing paycheck, promoting and hiring employees, updating employee profile and other typical HCM application transactions. All these transactions are well-defined in the PeopleSoft HR Self-Service 9.1 benchmark kit. This benchmark metric is the weighted average response search/save time for all the transactions. The PeopleSoft 9.1 Payroll (North America) benchmark demonstrates system performance for a range of processing volumes in a specific configuration. This workload represents large batch runs typical of a ERP environment during a mass update. The benchmark measures five application business process run times for a database representing large organization. They are Paysheet Creation, Payroll Calculation, Payroll Confirmation, Print Advice forms, and Create Direct Deposit File. The benchmark metric is the cumulative elapsed time taken to complete the Paysheet Creation, Payroll Calculation and Payroll Confirmation business application processes. The benchmark metrics are taken for each respective benchmark while running simultaneously on the same database back-end. Specifically, the payroll batch processes are started when the online workload reaches steady state (the maximum number of online users) and overlap with online transactions for the duration of the steady state. Key Points and Best Practices Two Oracle PeopleSoft Domain sets with 200 application servers each on a SPARC T4-4 server were hosted in 2 separate Oracle Solaris Zones to demonstrate consolidation of multiple application servers, ease of administration and performance tuning. Each Oracle Solaris Zone was bound to a separate processor set, each containing 15 cores (total 120 threads). The default set (1 core from first and third processor socket, total 16 threads) was used for network and disk interrupt handling. This was done to improve performance by reducing memory access latency by using the physical memory closest to the processors and offload I/O interrupt handling to default set threads, freeing up cpu resources for Application Servers threads and balancing application workload across 240 threads. See Also Oracle PeopleSoft Benchmark White Papers oracle.com SPARC T4-2 Server oracle.com OTN SPARC T4-4 Server oracle.com OTN PeopleSoft Enterprise Human Capital Management oracle.com OTN PeopleSoft Enterprise Human Capital Management (Payroll) oracle.com OTN Oracle Solaris oracle.com OTN Oracle Database 11g Release 2 Enterprise Edition oracle.com OTN Disclosure Statement Oracle's PeopleSoft HR and Payroll combined benchmark, www.oracle.com/us/solutions/benchmark/apps-benchmark/peoplesoft-167486.html, results 09/30/2012.

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Vertex Normals, Loading Mesh Data

- by Ramon Johannessen

My test FBX mesh is a cube. From what I surmise, it seems that the cube is on the extreme end of this issue, but I believe that the same issue would be able to occur in any mesh: Each vertex has 3 normals, each pointing a different direction. Of course loading in any type of mesh, potentially ones having thousands of vertices, I need to use indices and not duplicate shared verts. Currently, I'm just writing the normals to the vertex at the index that the FBX data tells me they go to, which has the effect of overwriting any previous normal data. But for lighting calculations I need more info, something that's equivalent to a normal per face, but I have no idea how this should be done. Do I average the 3 different verts' normals together or what?

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Flash game size and distribution between asset types

- by EyeSeeEm

I am currently developing a Flash game and am planning on a large amount of graphics and audio assets, which has led to some questions about Flash game size. By looking at some of the popular games on NG, there seem to be many in the 5-10Mb and a few in the 10-25Mb range. I was wondering if anyone knew of other notable large-scale games and what their sizes were, and if there have been any cases of games being disadvantaged because of their size. What is a common distribution of game size between code, graphics and audio? I know this can vary strongly, but I would like to hear your thoughts on an average case for a high-quality game.

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Oracle is #1 in the RDBMS Sector for 2011

- by jgelhaus

Gartner 2011 Worldwide RDBMS Market Share Reports 48.8% revenue share for Oracle (*) Gartner has published their market share numbers for 2011 based on total software revenues. According to Gartner, Oracle: is #1 in worldwide RDBMS software revenue share holds more revenue share than its seven closest competitors combined grew at 18.0%, exceeding both the industry average (16.3%) and the growth rates of its closest competitors. (*) Source: Market Share: All Software Markets, Worldwide 2011 by Colleen Graham, Joanne Correia, David Coyle, Fabrizio Biscotti, Matthew Cheung, Ruggero Contu, Yanna Dharmasthira, Tom Eid, Chad Eschinger, Bianca Granetto, Hai Hong Swinehart, Sharon Mertz, Chris Pang, Asheesh Raina, Dan Sommer, Bhavish Sood, Marianne D'Aquila, Laurie Wurster and Jie Zhang. - March 29, 2012

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Ask for Budget vs. Give Proposal

- by Miro

Should I ask a prospect what his budget is or just give out a price? He need: "a new web site, with nice effects but at same time very simple & funtional for my costumers & guests" It's a 5 page website for mp3 guided tour with 2-3 paragraphs of text on each page and 5-8 images on total + logo that needs redesign. It's my first 'over distance' job. (I don't know the guy personally and have never met him) Please let me know what is a good practice and how to proceed. P.S. Also what is an average price for Simple 5 page Flash website with some custom graphics. Thanks

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.NET 4: “Slim”-style performance boost!

- by Vitus

RTM version of .NET 4 and Visual Studio 2010 is available, and now we can do some test with it. Parallel Extensions is one of the most valuable part of .NET 4.0. It’s a set of good tools for easily consuming multicore hardware power. And it also contains some “upgraded” sync primitives – Slim-version. For example, it include updated variant of widely known ManualResetEvent. For people, who don’t know about it: you can sync concurrency execution of some pieces of code with this sync primitive. Instance of ManualResetEvent can be in 2 states: signaled and non-signaled. Transition between it possible by Set() and Reset() methods call. Some shortly explanation: Thread 1 Thread 2 Time mre.Reset(); mre.WaitOne(); //code execution 0 //wating //code execution 1 //wating //code execution 2 //wating //code execution 3 //wating mre.Set(); 4 //code execution //… 5 Upgraded version of this primitive is ManualResetEventSlim. The idea in decreasing performance cost in case, when only 1 thread use it. Main concept in the “hybrid sync schema”, which can be done as following: internal sealed class SimpleHybridLock : IDisposable { private Int32 m_waiters = 0; private AutoResetEvent m_waiterLock = new AutoResetEvent(false); public void Enter() { if (Interlocked.Increment(ref m_waiters) == 1) return; m_waiterLock.WaitOne(); } public void Leave() { if (Interlocked.Decrement(ref m_waiters) == 0) return; m_waiterLock.Set(); } public void Dispose() { m_waiterLock.Dispose(); } } It’s a sample from Jeffry Richter’s book “CLR via C#”, 3rd edition. Primitive SimpleHybridLock have two public methods: Enter() and Leave(). You can put your concurrency-critical code between calls of these methods, and it would executed in only one thread at the moment. Code is really simple: first thread, called Enter(), increase counter. Second thread also increase counter, and suspend while m_waiterLock is not signaled. So, if we don’t have concurrent access to our lock, “heavy” methods WaitOne() and Set() will not called. It’s can give some performance bonus. ManualResetEvent use the similar idea. Of course, it have more “smart” technics inside, like a checking of recursive calls, and so on. I want to know a real difference between classic ManualResetEvent realization, and new –Slim. I wrote a simple “benchmark”: class Program { static void Main(string[] args) { ManualResetEventSlim mres = new ManualResetEventSlim(false); ManualResetEventSlim mres2 = new ManualResetEventSlim(false); ManualResetEvent mre = new ManualResetEvent(false); long total = 0; int COUNT = 50; for (int i = 0; i < COUNT; i++) { mres2.Reset(); Stopwatch sw = Stopwatch.StartNew(); ThreadPool.QueueUserWorkItem((obj) => { //Method(mres, true); Method2(mre, true); mres2.Set(); }); //Method(mres, false); Method2(mre, false); mres2.Wait(); sw.Stop(); Console.WriteLine("Pass {0}: {1} ms", i, sw.ElapsedMilliseconds); total += sw.ElapsedMilliseconds; } Console.WriteLine(); Console.WriteLine("==============================="); Console.WriteLine("Done in average=" + total / (double)COUNT); Console.ReadLine(); } private static void Method(ManualResetEventSlim mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } } private static void Method2(ManualResetEvent mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } } } I use 2 concurrent thread (the main thread and one from thread pool) for setting and resetting ManualResetEvents, and try to run test COUNT times, and calculate average execution time. Here is the results (I get it on my dual core notebook with T7250 CPU and Windows 7 x64): ManualResetEvent ManualResetEventSlim Difference is obvious and serious – in 10 times! So, I think preferable way is using ManualResetEventSlim, because not always on calling Set() and Reset() will be called “heavy” methods for working with Windows kernel-mode objects. It’s a small and nice improvement! ;)

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T-SQL Tuesday - IO capacity planning

- by Michael Zilberstein

This post is my contribution to Adam Machanic's T-SQL Tuesday #004 , hosted this time by Mike Walsh . Being applicative DBA, I usually don't take part in discussions which storage to buy or how to configure it. My interaction with IO is usually via PerfMon. When somebody calls me asking why everything is suddenly so slow on database server, "disk queue length" or "average seconds per transfer" counters provide an overwhelming answer in 60-70% of such cases. Sometimes it can be...(read more)

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What is the etiquette in negotiating payment for a software development job

- by EpsilonVector

The reason I'm taking a general business question and localize it to software development is that I'm curious as to whether there are certain trends/etiquette/nuances that are typical to our industry. For example, I can imagine two different attitudes employers may generally have to payment negotiations: 1) we'll give you the best offer so we can't really be flexible about it because we already pretty much gave you everything we can give you, or 2) we'll give him an average offer and give in to a better one if forced to. If you try to play hard ball in the first attitude it'll probably cost you the job because you ask for more than they can give you, however if you don't insist on better payment in the second one you'll get a worse offer. In short, when applying to a typical job in our industry what are the typical attitudes from employers on the offers they give, what is the correct way to ask for a better payment, do these things differ between different types of companies (for example startups vs well entrenched companies), and how do these things differ between different kinds of applicants (graduate vs student)?

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My Thoughts On Twitter

- by andyleonard

This is a repost from my old blog. It kept showing up in search results when I looked for articles about Twitter and social networking, so I thought I'd share it here. :{> Introduction There's been lots of speculation about Twitter and what it means to the modern technologist. I've found some of it pretty insightful and some of it misinformed. I use Twitter . A bunch. Not as much as some , but more than average . I like it. The Best Defense... I don't intend to defend Twitter because I do not...(read more)

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Firefox is pounding my system what should I do

- by nikhil

I'm running the latest version of firefox 17.0.1 on ubuntu 12.10 on a Acer Aspire One 722 Netbook. It has an amd dual core C60 processor and 2GB RAM. As you can see, firefox is absolutely killing my system, it responds really slowly and opening tabs is a royal pain. I have on an average 4-5 open tabs at a given time. Is there something that I can do to make my browsing experience more zippy? Additionally I run the following addons Firebug HTTPS Everywhere Ad block plus

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Oracle FLEXCUBE delivers 'Bank-in-a-Box' with Oracle Database Appliance

- by margaret hamburger

Another great example of how Oracle Database Appliance simplifies the deployment of high availability database solutions making it easy for Oracle Partners and ISVs to deliver value added solutions to customers on a simple, reliable and affordable database platform. Oracle FLEXCUBE Universal Banking recently announced that it runs on Oracle Database Appliance X3-2 to deliver mid-size banks a compelling banking-in-a-box solution. With this certification, banks can benefit from a low-IT-footprint, high-performance, full-scale banking technology that is engineered to support end-to-end business requirements. In a recent performance test of Oracle FLEXCUBE Universal Banking on Oracle Database Appliance X3-2, the system managed more than 2.6 million online transactions in 60 minutes. This equated to roughly 744 transactions per second with an average response time of 156 milliseconds for 98 percent of the transactions. Likewise, the solution completed end-of-month batch processing for 10 million customer accounts in 123 minutes during the performance test. Learn more about Oracle Database Appliance Solution-in-a-Box.

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Microsoft Ramps up Security in Windows 8

To the average consumer, improvements in the realm of security may not have the most appeal with it comes to a new working environment such as Windows 8. After all, the operating system's future release is expected to offer such flashy bells and whistles as a nifty Metro interface, a tile-based Start screen that provides a quick jump to different functions, and much more. Although these stylish features may be what jumps out at first, it is going to be hard to deny the usefulness and virtual necessity of Windows 8's new security features. The number of consumers who have turned to the intern...

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Tuxedo Load Balancing

- by Todd Little

A question I often receive is how does Tuxedo perform load balancing. This is often asked by customers that see an imbalance in the number of requests handled by servers offering a specific service. First of all let me say that Tuxedo really does load or request optimization instead of load balancing. What I mean by that is that Tuxedo doesn't attempt to ensure that all servers offering a specific service get the same number of requests, but instead attempts to ensure that requests are processed in the least amount of time. Simple round robin "load balancing" can be employed to ensure that all servers for a particular service are given the same number of requests. But the question I ask is, "to what benefit"? Instead Tuxedo scans the queues (which may or may not correspond to servers based upon SSSQ - Single Server Single Queue or MSSQ - Multiple Server Single Queue) to determine on which queue a request should be placed. The scan is always performed in the same order and during the scan if a queue is empty the request is immediately placed on that queue and request routing is done. However, should all the queues be busy, meaning that requests are currently being processed, Tuxedo chooses the queue with the least amount of "work" queued to it where work is the sum of all the requests queued weighted by their "load" value as defined in the UBBCONFIG file. What this means is that under light loads, only the first few queues (servers) process all the requests as an empty queue is often found before reaching the end of the scan. Thus the first few servers in the queue handle most of the requests. While this sounds non-optimal, in fact it capitalizes on the underlying operating systems and hardware behavior to produce the best possible performance. Round Robin scheduling would spread the requests across all the available servers and thus require all of them to be in memory, and likely not share much in the way of hardware or memory caches. Tuxedo's system maximizes the various caches and thus optimizes overall performance. Hopefully this makes sense and now explains why you may see a few servers handling most of the requests. Under heavy load, meaning enough load to keep all servers that can handle a request busy, you should see a relatively equal number of requests processed. Next post I'll try and cover how this applies to servers in a clustered (MP) environment because the load balancing there is a little more complicated. Regards,Todd LittleOracle Tuxedo Chief Architect

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Nagios suddenly stops working

- by pankaj sharma

I have configure passive checks on one my host system for this i am using nsca. it was running fine. suddenly host is showing down on the monitoring. but host was fine and running when i check the logs on the host showing [1347941895] Warning: Attempting to execute the command "/submit_check_result host.example.com 'Current Load' OK 'OK - load average: 0.69, 0.53, 0.42'" resulted in a return code of 127. Make sure the script or binary you are trying to execute actually exists... i restarted nagios services many times but still it is showing the same error. can anyone help me regarding this. thanks in advance..

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Why does flush dns often fail to work?

- by Sharen Eayrs

C:\Windows\system32>ipconfig /flushdns Windows IP Configuration Successfully flushed the DNS Resolver Cache. C:\Windows\system32>ping beautyadmired.com Pinging beautyadmired.com [xxx.45.62.2] with 32 bytes of data: Reply from xxx.45.62.2: bytes=32 time=253ms TTL=49 Reply from xxx.45.62.2: bytes=32 time=249ms TTL=49 Reply from xxx.45.62.2: bytes=32 time=242ms TTL=49 Reply from xxx.45.62.2: bytes=32 time=258ms TTL=49 Ping statistics for xxx.45.62.2: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 242ms, Maximum = 258ms, Average = 250ms My site should point to xx.73.42.27 I change the name server. It's been 3 hours. It still points to xxx.45.62.2 Actually what happen after we change name server anyway? Wait for what? I already flush dns. Why it still points to the wrong IP? Also most other people that do not have the DNS cache also still go to the wrong IP

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How easily recognized are new TLDs?

- by Ryan Muller

I'm interested in purchasing a domain name for a new service I intend to market. I know that .com is instantly recognizable as a domain ending, and if I see stackoverflow.com I know it's a web address. However, I also recognize strings like github.io and mysite.tk as domains, since I've worked with domains like these. To the average member of the public, if one sees an address ending in .io or similar, non-mainstream TLD (e.g. on a billboard or business card) would they immediately know it's a URL and to type it into a browser? Or are these new domains only useful 1) for a technical audience or 2) when you will be primarily promoting your site through links and not print?

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