Questions related to improving application performance, this can be range from selection software architecture to selection of algorithms.

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0
votes
2answers
142 views

Static and dynamic data : should I use different databases?

Say I am building a website that uses two different types of data : Static : information that will hardly change, like movie awards or world countries names (I want fast access so no external API) ...
-1
votes
1answer
87 views

Huge long addition overhead compared to Native call?

A run a simple test JDK 1.7.0_45 (Windows 7, 64bit): Test 1: long start = System.nanoTime(); for (int i=0; i < 1000000; i++) { System.currentTimeMillis(); } elapsed = ...
6
votes
2answers
980 views

Should I group all of my .js files into one large bundle?

One of the difficulties I'm running into with my current project is that the previous developer spaghetti'd the javascript code in lots of different files. We have modal dialogs that are reused in ...
0
votes
4answers
361 views

What is the “1620's multiplication operation”?

I was stumbling through Wikipedia when I came across the entry for FLOPS, specifically the table in this section. The first entry is for a computer from 1961, the comment on the right reads The ...
3
votes
2answers
454 views

What's a good simple way to combat the n+1 problem?

I'm trying to better understand performance in PHP. One issue I'm thinking about is the n+1 problem. By n+1 I mean something like this: $posts = Posts::getPosts(); foreach($posts as $post) { ...
5
votes
1answer
309 views

Why does Haskell's built in max function run faster than mine?

I noticed that for some reason, Haskell's built in max function (which returns the greatest of two numbers) runs much faster than the one I wrote, even though they are essentially identical. From ...
1
vote
4answers
164 views

Track performance numbers

I have a (large) software project in a git repository. There is a benchmark suite that spits out lots of numbers (time per benchmark, allocations done per benchmark) I’d like to track. What is the ...
18
votes
4answers
907 views

How bad is it calling println() often than concatenating strings together and calling it once?

I know output to the console is a costly operation. In the interest of code readability sometimes it is nice to call a function to output text twice, rather than having a long string of text as an ...
4
votes
3answers
3k views

Data Oriented Design - impractical with more than 1-2 structure “members”?

The usual example of Data Oriented Design is with the Ball structure: struct Ball { float Radius; float XYZ[3]; }; and then they make some algorithm that iterates a std::vector<Ball> ...
5
votes
1answer
792 views

In Java, why use bit hacks when non-bitwise technique it is more readable?

Is there any legitimate use for bit manipulation hacks in higher-level languages such as Java? I can see them being useful in speed-sensitive low-level and computation-intensive programs, e.g. ...
-1
votes
1answer
882 views

get all the combination of a given set of numbers [duplicate]

I m trying to get the possible combinations of a given set of numbers say for example 123 The possible combinations would be 123 132 213 231 312 321 For this i have written a code as below - ...
0
votes
1answer
155 views

Power of 2 and performance in SQL Server

Many mathematical operation (such as division, multiplication, etc.) are supposed to be computed faster when dealing with power of two numbers (C++, C#?, ...) For instance 15 * 256 = 0x0e right ...
28
votes
10answers
3k views

Is template “metaprogramming” in Java a good idea?

There is a source file in a rather large project with several functions that are extremely performance-sensitive (called millions of times per second). In fact, the previous maintainer decided to ...
11
votes
4answers
408 views

Database design - Store state or compute state every time?

Let's say I have a relational database application and a "user" object and a "message" object. Now I want to show the number of unread messages to this user. What's the best way to archive this? Do I ...
1
vote
4answers
2k views

Is there a downside to using AggressiveInlining on simple properties?

I bet I could answer that myself if I knew more about tools to analyze how C#/JIT behaves but since I don't, please bear with me asking. I have simple code like this : private SqlMetaData[] ...
-2
votes
1answer
1k views

What is the best way to get a method name in runtime?

Here is a little background of my problem: I implemented a singleton logger class which is being called from several projects. I want to log the name of the class as well as the name of the method ...
3
votes
1answer
457 views

Why did Shannon's outguessing machine beat Hagelbarger's?

I'm reading "Rock Breaks Scissors", which describes two "outguessing machines" built at Bell Labs that try to exploit human non-randomness in the game of matching pennies. There was an outguessing ...
10
votes
3answers
4k views

Why use Android Fragments?

I have read the documentation and some other questions' threads about this topic and I don't really feel convinced; I don't see clearly the limits of use of this technique. Fragments are now seen as ...
0
votes
1answer
183 views

Good approach for hundreds of comsumers and big files

I have several files (nearly 1GB each) with data. Data is a string line. I need to process each of these files with several hundreds of consumers. Each of these consumers does some processing that ...
1
vote
2answers
141 views

Which is more expensive multiple conditional branches or multiple relational expression in a single condition?

Which is more expensive in terms of processing costs if ( x < 20 && z == "M") { // statements 3 } if ( x >= 20 && w && x <= 65) { // statements 1 } if( x ...
2
votes
2answers
183 views

How faster could a dedicated chip do sequential squaring modulo operations to break a time crypto capsule?

I'm facing a very real problem and, sadly, I cannot find the answer on my own: I'm hitting my limit as a programmer because my hardware knowledge is not sufficiently advanced at all. It's an issue ...
1
vote
2answers
418 views

Polling vs events pros and cons in JavaScript

I'm bit of a novice to JavaScript so I've been wondering on positive and negative sides of using polling compared to using events in JavaScript? When does one use one or the other? By polling I ...
0
votes
2answers
9k views

foreach in list or foreach in list.where [duplicate]

I don't know what to call this question. This is my example: foreach (var item in lstItem.Where(item => stock.ItemCode == item.ItemCode)) { stock.ItemName = item.ItemName; ...
0
votes
2answers
134 views

How should I create object after database insert PHP

I have just been working on a new project and doing things the same way I have for years now. However for the first time, I am constantly thinking about scalability and performance of both the ...
23
votes
7answers
5k views

Writing in C for Performance? [closed]

I know I have quite frequently heard that C typically has a performance advantage over C++. I didn't really think anything else of it until I realized that MSVC doesn't even seem to support the newest ...
0
votes
3answers
1k views

comparison of floating point numbers vs. comparsion of Integers in C [closed]

Does comparison of floating point numbers takes (considerably) longer time than comparison of Integers in C? I just wrote a C program of heap sort to sort floating point numbers. I am on ubuntu ...
0
votes
1answer
392 views

Using JDBC to asynchronously read large Oracle table

What strategies can be used to read every row in a large Oracle table, only once, but as fast as possible with JDBC & Java ? Consider that each row has non-trivial amounts of data (30 columns, ...
1
vote
3answers
1k views

Is there a performance difference between ++x over x++? [duplicate]

Is there a performance difference between using ++x over x++ increment operators? I've see developers use ++x in loops where I would normally write x++ out of habit. For example; for(int x=0; x ...
-4
votes
2answers
392 views

True/false on the left or the right? [duplicate]

I have heard that generally, an expression like: if (true === $variable) is faster than: if ($variable === true) My question is about the performance, not the readability. Questions such as this ...
1
vote
1answer
418 views

alternate approach of binary serialization/de-serialization

Is it possible to convert a list of object directly to byte[] (and vice versa) to gain performance (by avoiding serialization/de-serialization)? What I have in mind is that a list is somewhere in ...
0
votes
1answer
116 views

Performance of One API vs Multiple API's

I was having a conversation with a colleague and although my opinion makes sense to me, I wasn't able to back it up. I'm in the process of creating an API that will be hit hundreds of thousands of ...
0
votes
1answer
220 views

Can this argument be enough?

We have two C++ classes named Important and Small The class Small use a few methods and attributes from the class Important, but not all. Since our application is performance critical, instead of ...
1
vote
7answers
2k views

Is there any performance benefit in checking the item count prior to executing a foreach loop?

I saw this in code and was wondering if there is any performance benefit to checking the item count prior to looping: if (SqlParams.Count > 0) foreach (var prm in SqlParams) ...
1
vote
5answers
1k views

What are the advantages of recursion compared to iteration? [duplicate]

I'm trying to understand when is preferred to use recursion rather than iteration. Actually I've encountered recursion only in Javascript but never in Python. I imagine that recursion should be used ...
0
votes
1answer
917 views

ASP.net performance code behind vs app_code

I am wondering about performance of a web site/application when there is code in the code behind files rather than when the code is moved to separate files in the App_Code folder. My understanding ...
3
votes
1answer
149 views

Should a stored proc try to do more, in the attempt to avoid php mysql back and forth overhead

I have a REST architecture, running PHP on the server side which store and query a Mysql database. I am re-evaluating one architecture design decision: DECISION to re-evaluate: In an attempt to ...
1
vote
1answer
47 views

Performance and data retrieving

I'm currently developing a mobile application in Objective C for iOS devices. While doing the application I reach the point where I have to retrieve data from a database and show it on a table (the ...
0
votes
2answers
168 views

Whats a good structure to save and retrieve locations of images?

I got a java-ee application, where I collect informations about movies. Im my backend I provide data like the name, description, genre and a random uuid. I also got lots of related files, which are ...
23
votes
11answers
2k views

Does Refactoring towards Looser Coupling, Smaller Functions, and Separate Classes affect System Performance? (and Should I Care)

In Computer Science field, I have noticed a notable shift in thinking when it comes to programming. The advice as it stands now is write smaller, more testable code refactor existing code into ...
1
vote
5answers
389 views

Which statement performs best?

I was faced with this question by my team leader. Statement 1 (written by me): lnkbtn1.visible = lnkbtn2.visible = lnkbtn.visible = false; Statement 2 (written by my team leader): ...
2
votes
2answers
191 views

Will using multiple recordsets in one database request be more efficient?

I am redeveloping an old ecommerce website which is currently written in C# ASP.NET 2.0. Because this is a reasonably high volume website and has suffered performance issues I want to develop in the ...
0
votes
3answers
179 views

Indirection: Readability vs Performance [closed]

(I see there are a lot of similar questions, but answers are not really what I am interested at.) The thing that is bugging me is indirection. If I'm writing something, I do tend to inline as much ...
0
votes
1answer
64 views

Mail Server Caching

I'm currently working on a web mail client. When a user logs in, I'm fetching all the mails from the INBOX from the beginning of time. As expected this is pretty darn slow. I'm planning to implement ...
2
votes
3answers
137 views

Iteratively improve software architecture & quality in an agile process?

Or to put it another way how to ensure that architecture or quality doesn't suffer, doing agile. Some of the understandings in handling architecture in agile are below(generally applies to testing as ...
0
votes
3answers
334 views

Advantage of monitoring file change using Windows API rather than manually

I developed a Windows software about an year ago. Part of it was to monitor few configuration files for manual changes by user and if any of these change restart a particular service. So, I used the ...
3
votes
1answer
601 views

Hadoop and Object Reuse, Why?

In Hadoop, objects passed to reducers are reused. This is extremely surprising and hard to track down if you're not expecting it. Furthermore, the original tracker for this "feature" doesn't offer any ...
2
votes
3answers
504 views

Is Python suitable for a statistical modeling application looking over thousands of past events?

I'm currently working on a project with a partner where we analyze large datasets of past sporting events. There are approximately 30,000 events per year and we have historical data for five years. ...
0
votes
1answer
588 views

Most efficient multiple condition IF statement

I am using a function to compare over 100 variables inside of classes to each other an am curious if one method of comparing multiple condition statements is more efficient than another. I am ...
0
votes
3answers
2k views

Super Fast File Storage Engine

I basically have one big gigantic table (about 1.000.000.000.000 records) in a database with these fields: id, block_id, record id is unique, block_id is not unique, it contains about 10k (max) ...
0
votes
1answer
106 views

How to convey your approach is faster than the built-in, alternative approaches? [closed]

Imagine you have a tool that's much faster than another one (built-in, alternative). You want to mention this in the description of the tool so people can see the point of your tool existing. By ...