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

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1answer
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Improving performance for web scraping code

I have a website in which the code scrapes other websites for getting the accurate data. While the code works good but there a decent lag in performance because the code firsts downloads the html ...
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4answers
2k views

JSF for an internet facing, high traffic web application

I, perhaps, made a wrong choice of going with a Component-based Framework like JSF for an internet facing, high traffic web application. Development with JSF has although been easier but what I fear ...
7
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4answers
648 views

Is there a performance benefit to using immutable objects in a scripting language?

As I understand it, writing your objects in an immutable style can help the performance of your program for compiled languages, as the compiler tends to rewrite your code in single static assignment ...
4
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2answers
161 views

Is performance testing applicable to a QA or business user testing?

Performance testing is something that I, as a developer do when optimizing. However, if the change is purely optimization, should the QA or business user perform their own performance testing? I would ...
8
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2answers
2k views

Eclipse runs my java program 6 times faster… Can I achieve this performance without using it?

I've written a java program that generates all repetitive permutations based on the characters and the length given. When I execute my code in Eclipse, it generates a file with 1,000,000 permutations ...
0
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1answer
165 views

Data structure to use for complex lookups in an event engine?

What would be an optimal way to organize arbitrary data types into a structure that allows for complex (non-index based) lookups into the data without performing full loop-through's? For a little ...
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7answers
215 views

Throwing an Exception if a Query Doesn't Use an Index

I'm working on a largish webapp that was developed by several other programmers and I keep running into performance issues caused by poorly written SQL queries and queries that don't use an index. ...
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4answers
2k views

How do I speed up XML parsing operation?

I currently have a php script set up to do some xml parsing. Sometimes the script is set as an on page include and other times it is accessed via an ajax call. The problem is the load time for this ...
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2answers
517 views

Session size management

From what I know, the session information is usually saved on the server. In Java the data is handled as a Map which I guess contains the a String identifier and an object reference which points to a ...
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2answers
183 views

Where can I find good example of techniques to compact data in-memory? [closed]

I'm writing a Java framework to manipulate a large amount of data in-memory, where many "cells" that are near each other will have the same value. I'm looking for algorithms and/or techniques ...
3
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1answer
204 views

How to optimize methodology to collect Market Data?

I am working on Application which goes and get's market data from different sources, I am using polling mechanism where vendor/broker put his data file and my application would go and hit that ftp ...
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1answer
212 views

Where is a good place to start to learn about custom caching in .Net

I'm looking to make some performance enhancements to our site, but I'm not sure exactly where to begin. We have some custom object caching, but I think that we can do better. Our Business We ...
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5answers
16k views

Performance of Scala compared to Java

First of all I would like to make it clear that this is not a language-X-versus-language-Y question to determine which is better. I have been using Java for a long time and I intend to keep using it. ...
9
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4answers
295 views

Is it a good idea to measure the performance of a method by using unit test timeout?

In a project where there are non-functional requirements which specify the maximum execution time for a specific action, QA must check the performance of this action on a dedicated machine using ...
5
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1answer
724 views

Coded ui to measure performance

I have been tasked with using coded UI to measure performance on a proprietary windows desktop application. The need is to measure how long it takes for the next page/screen to display after a user ...
6
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1answer
352 views

Should web browsers include popular web framework libraries?

What reasons are there for web browsers to not have a library of popular web frameworks. For example if a web page included jQuery, why shouldn't the browser have it's own static version, which is ...
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5answers
2k views

Resources on Writing Efficient C Code for Micro-controllers? [closed]

Serious help needed here. I love programming. I've been reading bunch of books(such as K&R) and articles/forums online for C language lately. Even tried looking into Linux code(although, i was ...
4
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3answers
601 views

Question about a “Benchmark” regarding Java and .NET

To get that out of the way - i am not asking about which platform is faster or try to start a flame war. Question: Why is the .NET version slower 5x in the first test ? The results i got were: .NET ...
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2answers
3k views

How can I separate the user interface from the business logic while still maintaining efficiency?

Let's say that I want to show a form that represents 10 different objects on a combobox. For example, I want the user to pick one hamburguer from 10 different ones that contain tomatoes. Since I want ...
9
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6answers
594 views

Examples of general purpose algorithms that have benefited from running on a GPU? [closed]

I am looking for examples of general purpose algorithms (meaning non-graphics related) that have been proven to run an order of magnitude faster on a GPU than on a CPU. I will use these examples to ...
3
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2answers
195 views

What percentage of code and runtime do you typically allow for testing?

When I write code, a certain amount of it is just for the purpose of logging, tracing, or otherwise "testing" what the program is doing. This not unit testing; this is not when it is running in ...
4
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2answers
2k views

InterviewStreet (Vertical Sticks) just a tip where to get started

Having a lot of trouble with this question in interviewstreet.com: Given array of integers Y=y1,...,yn, we have n line segments such that endpoints of segment i are (i, 0) and (i, yi). Imagine that ...
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3answers
109 views

Should I decompress zips before I archive?

I am writing a small personal archiving tool. I frequently work with a lot of client databases for short periods, what my tool will do is in overnight batch jobs it will detach the database and zip up ...
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3answers
3k views

What performance can we expect from std::string's c_str()? Always constant time?

I've been doing some needed optimizations lately. One thing I've been doing is changing some ostringstreams -> sprintfs. I'm sprintf'ing a bunch of std::strings to a c style array, ala char foo[500]; ...
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2answers
223 views

Algorithm for searching the neighbors neighbor of a directed graph

Is there an algorithm to search a directed graph (tree) for its neighbors neighbor? My current brute-force solution works as follows: for each node n: for each child c of n for each parent ...
6
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3answers
8k views

Practical size limits of a Hashtable and Dictionary in c#

What are the practical limits for the number of items a C# 4 Dictionary or Hashtable can contain and the total number of bytes these structures can reasonable contain. I'll be working with large ...
4
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1answer
474 views

Is there a formula to figure out the total execution time of sequential asyncronous processes?

I have a set of steps that need to run sequentially over a list of data. However each step only operates on a single piece of data at a time. Because of this, I can run the steps asynchronously. For ...
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4answers
4k views

Increase Performance of VS 2010 by using a SSD [closed]

After searching on the internet for performance improvements when using Visual Studio 2010 with a solid state hard drive, I heard a lot of different opinions. A lot of people said that there isn't ...
2
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3answers
229 views

How should we deal with multiple transaction-report requests?

We are developing a system for the retail market and of its features will enable clients (actually consumer clubs) to go through all transactions made by end-clients. One of the ways to get this ...
2
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4answers
273 views

How one could use a live editor

I was thinking about a live editing environment where code / a source file is synchronized so that changes made by one user would be carried across to all others editing the file. Something like ...
7
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2answers
259 views

What are the benefits of archiving?

I always see sites that only keeps fresh content on the home or subsections, and the rest of the content is kept in a separate section called 'archive'. Recently I have also heard that NoSQL DB's ...
5
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4answers
2k views

Why scalability issues cannot be solved by more servers ?

I know that big websites suffer from scalability issues and I guess that more servers (hardware) can help to handle scalabililty issues but I see that big websites are stuck about scalability even if ...
5
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4answers
424 views

One stop shop for good coding practices and performance tips? [closed]

While this may be a very subjective question I was wondering if there's a place (or many places) on the web where one can read up about good coding and performance tips for different languages and how ...
3
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5answers
758 views

Good techniques to speed up database execution

I have an ASP.Net application that is using a MySQL database. My queries are not executing as fast as I would like them too. Are there some standard ways to increase the speed of a MySQL database ...
0
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4answers
249 views

Count a row VS Save the Row count after each update

I want to know whether saving row count in a table is better than counting it each time of the proccess. Quick Example : A visitor goes to Group Clan, the page displays clan information and Members ...
1
vote
3answers
543 views

How to design a performance comparison between two data structures

I want to compare the performance of two search trees of integers (an AVL tree and a RedBlack tree). How should I design/engineer the tests to accomplish this? For example, let's consider the insert ...
4
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3answers
278 views

For performance critical situations is storing file metadata in a database better?

As per the title of this question, for extremely performance critical situations, is storing a file's metadata (e.g. location, size, download on, etc) in a database going to allow for better ...
3
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1answer
367 views

Specifically for JS, CSS, HTML: what is the difference between optimization, compression, minification, tidying, concatenation?

When we talk about source code and the file which contains the code like CSS, HTML, JavaScript and we also talk about performance of a web site or application, what is the differences between these ...
16
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1answer
10k views

What is the difference between btree and rtree indexing?

I've noticed on MySQLWorkbench that you can choose how to store your indexes before forward engineering your design. The storage types are: BTREE RTREE HASH Researching this, I found some ...
5
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6answers
675 views

How should I react to diminishing application performance?

Sometimes it comes to me that the biggest challenge for an engineer when he find his application getting worse in performance is lack of enough information. Imagine that you go through the weekly ...
20
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6answers
3k views

C++ Renaissance - marketing slogan? [duplicate]

Possible Duplicate: What does the latest “C++ Renaissance” mean? Lately, I hear a lot about C++ Renaissance. What is that? C++ is currently undergoing a renaissance. This ...
33
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18answers
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How can dev teams prevent slow performance in consumer apps?

When I previously asked what's responsible for slow software, a few answers I've received suggested it was a social and management problem: This isn't a technical problem, it's a marketing and ...
9
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7answers
2k views

Would using AJAX extensively improve server performance?

Clearly AJAX improves the user interface but does this also decrease server load? You would think it does because the entire page will not have to be served up each time, but maybe there are other ...
23
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14answers
3k views

Why do so many developers believe performance, readability, and maintainability cannot coexist?

While responding to this question, I began to wonder why so many developers believe a good design should not account for performance because doing so would affect readability and/or maintainability. ...
4
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8answers
1k views

Are Bools/Bits Faster Than Integers

As the title suggests I'm wondering whether bools or bits are faster than using integers (1 and 0)? Specifically I thinking about their speed in CASE statements, even more specifically in T-SQL ...
6
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4answers
536 views

What are the options when Sql generated by ORM needs tuning?

I am starting working on a web project using django. While researching whether to use Sqlalchemy or raw sql when django orm is not sufficient which is also a question I asked here Raw Sql vs ...
56
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14answers
10k views

Why would it ever be possible for Java to be faster than C++?

Sometimes Java outperforms C++ in benchmarks. Of course, sometimes C++ outperforms. See the following links: http://keithlea.com/javabench/ ...
5
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4answers
3k views

Big-O for nested loop

I am reading this post on Big-O It says that the following code is O(n^2): bool ContainsDuplicates(String[] strings) { for(int i = 0; i < strings.Length; i++) { for(int j = 0; j ...
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6answers
259 views

Complexity vs maintainability in modern hardware

Today with the modern hardware and memory coming cheap, how much sense does it make to spend effort to analyze algoriths or data structure complexity? Wouldn't it be better instead, to focus on clean, ...
5
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2answers
827 views

Erlang or 'x'.. Is it worth it (vs. Python w/ GIL)?

So, I've finally gotten myself to a point where I'm comfortable enough with Python (using Pyramid as my framework of choice) to undertake a rather large personal project. As it's a personal project, I ...