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

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2answers
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How to find local maxima in matrices?

I need to develop an algorithm for finding all the local maxima in a two-dimensional array: how to search for local maxima in the the most efficient way? Are there algorithms about it? Moreover, the ...
-1
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1answer
189 views

Banking Applications need Auto save? [closed]

We are developing a banking application. It's internal project of the bank. The application has to capture huge data to process. So auto save is recommended approach to capture? How to perform ...
1
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1answer
848 views

Performance overhead of standard containers and boost [closed]

Adap.TV has chosen C++ to develop their software. However, they've decided not to use the standard containers1 and boost for performance reasons, as they've blogged about it in the following article: ...
4
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3answers
1k views

Anonymous function performance - setTimeout

According to Gregory Baker & Erik Arvidsson (Google), creating a named function and then passing that to setTimeout is actually faster than creating an anonymous function (reference: Optimizing ...
5
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2answers
1k views

Performance and other issues with using floating point types in C++

Being interested in C++ performance programming there is one aspect I really have no clue about- and that is the implications of using floating point calculations vs doubles vs normal integer ...
4
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3answers
536 views

How Immutable Sets are Manipulated

When working with an immutable set or map, like the ones found in many functional programming languages, operations that would otherwise modify the container generate a new container instead. I know ...
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4answers
760 views

Read K&R before learning low latency C++?

I have never really done a large amount of C programming but am in the middle of teaching myself low latency C++. Would it do more harm than good to read the K&R C programming book? I am a bit ...
2
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1answer
551 views

Is there's a way to speed up my php code which parse XML files

I'm developing a web application and we are using XML as a database and I'm using Linux as a platform and centos 6.5 as a server. Changing some value would make a lot a lot of changes in about six XML ...
5
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1answer
1k views

How much usage of “likely” and “unlikely” macros is too much?

The often known as likely and unlikely macros help the compiler know whether an if is usually going to be entered or skipped. Using it results in some (rather minor) performance improvements. I ...
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2answers
938 views

C++ Typecasting VS performance

Let's say we're designing a video game. We have some sprites on the map and we want to call some method of the particular sprite at some particular position. We are using one broadly-known C++ ...
1
vote
1answer
314 views

Table scaling with partitions or with separate databases?

Let's say I have a table (let's call it BigTable) which could experience 5,000,000 INSERTS per day (with possibly just as many SELECTs). Each row inserted is about 50kb. These daily INSERTs are ...
6
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3answers
907 views

A question regarding linked list vs vector insert/remove results comparison

I was reading this blog post: http://kjellkod.wordpress.com/2012/02/25/why-you-should-never-ever-ever-use-linked-list-in-your-code-again/ and I found there a code to run: http://ideone.com/62Emz ...
2
votes
1answer
519 views

How best to merge/sort/page through tons of JSON arrays?

Here's the scenario: Say you have millions of JSON documents stored as text files. Each JSON document is an array of "activity" objects, each of which contain a "created_datetime" attribute. What is ...
2
votes
1answer
597 views

Internationalization through SQL Database and performance issues

I'm using .Net technologies and because ASP.Net "instant translation" is not really easy to do with ResX, since it has to be compiled after every change, there are a few hacks available ...
3
votes
2answers
2k views

Why is NoSQL better for this scenario?

Hypothetical scenario: Let's say we are downloading JSON from Facebook with details of a user's friend's checkins, posts, etc... These come in as one document per friend per activity, so with 8 ...
10
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4answers
12k views

What is the point of using lists over vectors, in C++?

I've run 3 different experiments involving C++ lists and vectors. Those with vectors proved more efficient, even when a lot of insertions in the middle were involved. Hence the question: in which ...
6
votes
2answers
584 views

Does javascript support numerically indexed arrays with a more optimized algorithm than an associative array?

I know that Python, Perl, Java, Lua and obviously C (as it's the only array that's in ANSI standard afaik) support faster looking of numerically indexed arrays than doing a hash lookup or anything ...
2
votes
1answer
226 views

How to communicate inefficiency before it's implemented?

This is a problem I come across pretty often. Basically we are using an application to make art content. Often times this requires writing custom tools for it. Sometimes you run into parts of the ...
4
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4answers
235 views

What performance topics should I be aware of? [closed]

When coding performance-critical portions of code (not necessarily large, but code that gets executed a lot), what topics should I be aware of/take into account. I'm already fairly familiar with ...
1
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2answers
631 views

Parsing a Log File - Java

Im reading a log file in Java on a Linux box on a continual schedule of 2 minutes looking for certain messages. I store the last offset (RandomAccessFile getFilePointer) and read from it onwards when ...
3
votes
1answer
484 views

Java Logfile Parsing Assistance

I'm writing a log parser that continuously looks for specific patterns and then fires off events to another system when it finds these matches. The firing of the event is time critical to catch errors ...
4
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2answers
6k views

Low Latency Unix/Linux

Most low latency/high frequency programming jobs (based on job specs) appear to be implemented on unix platforms. In a lot of the specs they make particular request for people with "low latency linux" ...
3
votes
1answer
2k views

Cost of setInterval in Javascript

I've got some code that I want to run when certain HTML elements are added to the page. To do this, I have a "runOnRender" function: runOnRender: function (func, args, interval) { var ...
7
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2answers
409 views

Shared Cache - Invalidation Best Practice

I'd like to know what would be a better approach to invalidate/update cache objects. Prerequisites Having remote memcached server (serving as cache for multiple applications) All servers are hosted ...
3
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1answer
398 views

Aggregate Root and Lots of Data Efficiency

It's more of a scenario, but it isn't far fetched at all. Let's say I have an Aggregate Root (AR) Warehouse which it's used to manage product stock. The Product itself is an AR in a different bounded ...
1
vote
1answer
331 views

Effective implementation of “array” of type Int X String -> String in .NET or in general

The question in general is: is there a more effective way of implementation of table with structure like Dictionary<int, Dictionary<string, string>>? The reason I am asking this is ...
6
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2answers
416 views

Versioned Resources to Improve Cacheability

Here's an API concept which could be useful for performance optimisation. It's an example of key-based cache expiry applied to a broader internet-wide context instead of the internal Memcached-style ...
8
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3answers
389 views

Would it be better to have extra checks, or would it be a waste of time?

In your opinion, do you think it is a waste of time to make checks that you know there is no possible way of it being there/not being there, or would you just put it there just in case there is a bug ...
3
votes
2answers
807 views

Memory management for fast message passing between threads in C++

Suppose there are two threads, which communicate by asynchronously sending data messages to each other. Each thread has some kind of message queue. My question is very low level: What can be expected ...
4
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4answers
624 views

Having error codes option in C++ library for performance

I have written an open source and cross-platform C++ File Library which have exception and error codes. Exceptions can be disabled when the program is running. In that case, the user have to check the ...
22
votes
5answers
930 views

Multiple database accesses or one massive access?

What is a better approach when it comes to performance and optimal resource utilization: accessing a database multiple times through AJAX to only get the exact information needed when it is needed, or ...
11
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8answers
1k views

Does low latency code sometimes have to be “ugly”?

(This is mainly aimed at those who have specific knowledge of low latency systems, to avoid people just answering with unsubstantiated opinions). Do you feel there is a trade-off between writing ...
0
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2answers
869 views

Idea to develop a caching server between IIS and SQL Server

I work on a few high traffic websites that all share the same database and that are all heavily database driven. Our SQL server is max-ed out and, although we have already implemented many changes ...
3
votes
3answers
315 views

Is it ok to ignore poor performance for a resource that will be cached?

Let's say I have a web service that is poorly written and inefficient, but it's output is cached so there's no bottleneck. Do you just leave it? Would you go as far as to take deliberate shortcuts ...
2
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2answers
161 views

Browser support for internal corporate tools

We are on the verge of a conversion. For years, our company supported only IE for its internal (intranet) home-built tools. Since a few of our users are still on XP, which means IE only goes up to ...
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2answers
298 views

Store image as logic file (in db by using binary format) or physical file (in the server) [duplicate]

Possible Duplicate: what are the best tips for storing images in a database? In those study cases of image storage, An image that change only once in a while, if it changes at all (like ...
2
votes
1answer
689 views

Strategy to find bottleneck in a network

Our enterprise is having some problem when the number of incoming request goes beyond a certain amount. To make things simpler, we have N websites that uses, amongst other, a local web service. This ...
0
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1answer
135 views

Is there a perf hit using mule as a container vs. standard JEE container like Weblogic?

Our team is considering using Mule in a large scale medium volume internal facing transactional banking application. At first Mule would just be used as an application server although it is possible ...
3
votes
2answers
4k views

How to design a scalable notification system? [closed]

I need to write a notification system manager. Here is my requirements: I need to be able to send a Notification on different platforms, which may be totally different (for exemple, I need to be ...
1
vote
1answer
129 views

Strategy for clients to retrieve real-time log from HTTP server

I have an HTTP Server Service application which has its own logging mechanism. It's written in Delphi. I would like to provide a way for multiple clients to connect to this service and get a real-time ...
8
votes
7answers
1k views

Is Java much harder to “tweak” for performance compared with C/C++?

Does the "magic" of the JVM hinder the influence a programmer has over micro-optimisations in Java? I recently read in C++ sometimes the ordering of the data members can provide optimizations ...
47
votes
10answers
3k views

When does “proper” programming no longer matter?

I've been building an android game in my spare time. It's using the libgdx library so quite a bit of the heavy lifting is done for me. While developing, I carelessly selected datatypes for some ...
2
votes
1answer
218 views

What is the most performant CSS property for transitioning an element?

I'm wondering whether there is a performance difference between using different CSS properties to translate an element. Some properties fit different situations differently. You can translate an ...
-3
votes
2answers
924 views

Java performance of StringBuilder append chains [closed]

In Java, if I am building a significant number of strings, is there any difference in performance in the following two examples? StringBuilder sb = new StringBuilder(); for (int i = 0; i < ...
-2
votes
1answer
166 views

Performance impact of not implementing relationships at the database level? [closed]

Let's imagine a data model with customers and invoices. There is a 1 to n relationship between a customer and its invoices. We uses an ORM (like Hibernate). One can explicitely implement the 1-n ...
2
votes
4answers
225 views

Which would be the best platform to develop websites to be used with very slow connections without sacrificing too much the design? [closed]

How can we give dial-up users in some remote places or less developed countries, a good experience while using dynamic websites.
0
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1answer
662 views

Increase application performance [closed]

I'm writing a program for a company that will generate a daily report for them. All of the data that they use for this report is stored in a local SQLite database. For this report, the utilize ...
1
vote
1answer
384 views

DDD Model Design and Repository Persistence Performance Considerations

So I have been reading about DDD for some time and trying to figure out the best approach on several issues. I tend to agree that I should design my model in a persistent agnostic manner. And that ...
19
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7answers
1k views

Does software rot refer primarily to performance, or to messy code?

Wikipedia's definition of software rot focuses on the performance of the software. This is a different usage than I am used to; I had thought of it much more in terms of the cleanliness and design of ...
5
votes
1answer
594 views

How can I compute the Big-O notation for a given piece of code? [closed]

So I just took a data structure midterm today and I was asked to determine the run time, in Big O notation, of the following nested loop: for (int i = 0; i < n-1; i++) { for(int j = 0; j < ...