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

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2
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1answer
122 views

Is doing some work for credit worthwhile?

Not sure how to title this as it's not just about that. But suppose that there is a software like .NET BCL, and you notice some places where you can make things much faster. It's not a great example ...
3
votes
2answers
380 views

Methods to identify and resolve memory leaks in the JVM

As the data is migrated via the object level, there has been a slow upwards trend in memory usage. I can see the periodic gc activity, but the memory trend is still going up slowly. I have currently ...
1
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2answers
229 views

How fast should a Python factoring script be?

Just how efficient is "good enough" for all intents and purposes? I wrote a script to simply list off all numbers that divide into an input, x, as pairs (i, n//i) and was just curious how efficient I ...
9
votes
3answers
3k views

Java Heap Allocation Faster than C++

I already posted this question on SO and it did ok. It was unfortunately closed though(only needs one vote to reopen) but someone suggested I post it on here as it is a better fit so the following is ...
1
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6answers
560 views

Benchmark of asynchronous code

Asynchronous programming seems to be getting quite popular these days. One of the most quoted advantages is performance gain from removing operations that block threads. But I also saw people saying ...
1
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3answers
419 views

Add javascript to all pages (for caching), or only to the pages that require the scripts (for a smaller page size)?

I'm using bits of javascript on my website for an image gallery, smooth scrolling, etc. These scripts are not used on every page (not every page has an image gallery for example). However, the scripts ...
0
votes
2answers
248 views

Is this a good measure of PHP script usage of the system?

I've been trying to see a way to get a measure of how much a PHP script costs of memory to the server. Well, I've found some solutions out there that requires some software to make tests and even ...
1
vote
1answer
185 views

Improving the efficiency of containers with dynamically allocated objects

This is not strictly related to C++ but its type system serves to illustrate the problem well. Assume: We have a generic template Container<T> (such as a std::vector<T>) which stores an ...
2
votes
3answers
241 views

Will object reuse optimize this often-called function?

Suppose I have a function that I need to call a lot, maybe a few thousand times on every mouse down or mouse move. It uses an instance of a function (class), called Transform: function func1(a, b, c) ...
10
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7answers
405 views

When to start thinking about scalability? [closed]

I'm having a funny but also terrible problem. I'm about to launch a new (iPhone) app. It's a turn-based multiplayer game running on my own custom backend. But I'm afraid to launch. For some reason, I ...
1
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2answers
182 views

When to really focus on performance?

We've just finishing up the first release of a database driven web application, which is now in regression testing. The application has an advanced search with many different filtering criteria. When ...
0
votes
1answer
353 views

Python — Time complexity of built-in functions versus manually-built functions in finite fields

Generally, I'm wondering about the advantages versus disadvantages of using the built-in arithmetic functions versus rolling your own in Python. Specifically, I'm taking in GF(2) finite field ...
1
vote
2answers
540 views

Static vs. dynamic memory allocation - lots of constant objects, only small part of them used at runtime

Here are two options: Option 1: enum QuizCategory { CATEGORY_1(new MyCollection<Question>() .add(Question.QUESTION_A) .add(Question.QUESTION_B) ...
5
votes
2answers
333 views

Structuring Access Control In Hierarchical Object Graph

I have a Folder entity that can be Moderated by users. Folders can contain other folders. So I may have a structure like this: Folder 1 Folder 2 Folder 3 Folder 4 I have to ...
9
votes
3answers
507 views

When is it a good time to reason about performance in Haskell?

Simon Peyton Jones himself recognizes that reasoning about performance in Haskell is hard due to the non strict semantics. I have yet to write a significant project in haskell so I wonder: can I ...
8
votes
2answers
384 views

Is there a comparative study of the memory consumption of programming languages runtimes, correlated with expressiveness and production bug ratios? [closed]

There are many comparative studies and available online when it comes to the runtime performance of applications built using one language or another. Some driven by corporations, some academic, some ...
4
votes
4answers
2k views

Server-side vs Client-side web application Performance [closed]

I am an entry level programmer with only a few months of experience. Yesterday I was discussing with a colleague how we can improve the performance of a project we are working on together. The ...
0
votes
0answers
72 views

Efficient Copy While Sorting

I have an algorithms library called NDex. I am in the process of upgrading it to a new version. Part of this upgrade involves providing two versions of many algorithms: an in-place version and a ...
6
votes
4answers
629 views

Is it a performance hit to create threads that loop a lot to check for things?

This is a generic question that I've always wondered. In general, is it intensive for a CPU to create threads that perform "while not true ..." loops or similar? For example, suppose I do: // ...
0
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2answers
208 views

The best way of coding web system in term of performance [closed]

So far I've been using IPB and my custom scripts all coded in PHP but I am really disappointed of the long term performance of it. I would like to move to native coding, the learning time to put into ...
-1
votes
5answers
461 views

The emperor's new code, or: how to communicate code efficiencies [closed]

So you've made some code changes that should hopefully speed up some part of an application. But there is just one problem - you don't know how it will perform in live. Different networks, different ...
5
votes
1answer
294 views

How can I benchmark concurrent key-value stores?

I have some concurrent key-value store implementations that are implemented with hash tables and search trees that I would like to compare. I would like to benchmark them with a real world application ...
3
votes
2answers
511 views

How is it possible to build the whole codebase from source at Google scale?

The first answer to an old, recently active question linked to a video which talks about how Google repository is done. One interesting thing which was mentioned is the fact that everything is build ...
1
vote
1answer
193 views

parallel computing list of objects

I have a list of objects that all require the exact same filtering, basically a set of conditionals in a function which outputs if the object is "good" or "bad". I want to keep all of my "good" ...
6
votes
4answers
321 views

Issues to be considered while loading jQuery?

I have seen many answers in SO regarding using Google's CDN to load jQuery instead of loading it from the local server. In essence I understand this is the issue related with decreased latency, ...
0
votes
1answer
88 views

How to find the running time of an algorithm that involves heuristics

I am working with A* algorithm, in which I have a 2D grid and given two points, find the shortest distance between them, while not running into any obstruction. Now, for each cell, I find the ...
4
votes
2answers
444 views

caching on multiple servers

Because we need to keep response times low, we get tons of requests, and we need to basically process ALMOST the same data (which I'll refer to as X) each request (the inputs are different though, so ...
5
votes
3answers
441 views

Performance considerations when using Go for my project

I'm looking at using Go (aka golang) for a project (a SQL database, but that mostly doesn't matter here) where performance is critical, but under low load the primary bottleneck will be I/O to disk. ...
0
votes
2answers
1k views

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
votes
1answer
171 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
vote
1answer
723 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: ...
2
votes
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 ...
4
votes
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
votes
3answers
472 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 ...
0
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4answers
675 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
votes
1answer
469 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
votes
1answer
811 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 ...
1
vote
2answers
748 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
291 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
votes
3answers
738 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
485 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
519 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
1k 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 ...
7
votes
4answers
8k 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 ...
7
votes
2answers
512 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
votes
4answers
230 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
vote
2answers
566 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
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1answer
398 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
5k 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" ...