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

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4
votes
1answer
35 views

When designing a replacement application, how can I compare its performance to the original, if there are no existing statistics?

I don't believe there are any performance statistics kept for the application I'm being asked to replace, and don't want to ask the individuals doing the work to manually record things like how long ...
7
votes
3answers
449 views

Enterprise software: Where should the code go? [duplicate]

I recently went for an interview with a software company that claims to write enterprise level software. During the interview, the interviewer remarked that its better to use the database simply to ...
0
votes
3answers
148 views

Compile-time vs. run-time configuration

I'm starting new project and need to decide on how to handle configuration. I recently run into suckless project. While it has its own issues, I really liked its approach to configuration - just a ...
2
votes
3answers
171 views

fast, say O(log2(N)), sliding median algorithm

So I know how to do a fast O(log2(N)) sliding max or sliding min algorithm. Brookes: "Algorithms for Max and Min Filters with Improved Worst-Case Performance" IEEE TRANSACTIONS ON CIRCUITS AND ...
2
votes
2answers
4k 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 ...
1
vote
4answers
147 views

List comparing techniques for faster performance

I need to cross names from two lists, and find all occurrences of one name in the other. The lists are too big, one have 50k elements and the other 400k. For a small list I would use two foreach ...
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 ...
1
vote
1answer
114 views

Are there real world examples demonstrating reasonable performance improvement by using move semantics?

(I've asked a similar question on SO but unfortunately it might not be proper, so I also put here; please kindly point out if you think it's a duplicate.) I've heard many words about the move ...
1
vote
1answer
92 views

Excel worksheet population and fomatting is slow

I have written a VSTO plugin in C# which populates several worksheets. During the population process cell values or formula are added one at a time according to user-definable criteria taken from a ...
2
votes
1answer
408 views

How many Angular Controllers and/or Directives is too many?

I'm building a large, editable data table with angular, and I'm trying to figure out what the best practice is. The table will be a couple of hundred rows, with a couple of dozen columns, so upwards ...
0
votes
1answer
60 views

What is the explication for the difference execution time for the same instruction?

As you know when we run instruction in our code like long a = b; we will not have the same ticks each to be executed. first exeution it take 2ticks; second exeution it take 3ticks; third exeution it ...
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
1answer
50 views

Does grouping threads by task improve performance?

This is kind of a lazy question on my part, since I gave up after trying only a few google terms. But when I read about multi-threaded performance, I read about context switching being bad for ...
1
vote
1answer
117 views

Correct usage of Bluebird promise

This is related to this question on promise performance. The current top answer states that using new Promise is an anti-pattern in bluebird And that promisify should be used instead. I ...
6
votes
1answer
242 views

Why are native ES6 promises slower and more memory-intensive than bluebird?

In this benchmark, the suite takes 4 times longer to complete with ES6 promises compared to Bluebird promises, and uses 3.6 times as much memory. How can a JavaScript library be so much faster and ...
2
votes
2answers
73 views

Is using triggers best solution for this scenario

A large SQL transactional database has more than 100 tables (and it will grow). One of them is called Order. Then, there is another table WorkLoad which derives from Order and many other joined table ...
13
votes
1answer
306 views

Is there a performance benefit to using the method reference syntax instead of lambda syntax in Java 8?

Do method references skip the overhead of the lambda wrapper? Might they in the future? According to the Java Tutorial on Method References: Sometimes... a lambda expression does nothing but ...
3
votes
1answer
104 views

Can SSE (or AVX) be used to do large bsf?

I'm faced with having to do a bsf (find the first bit set) in a 512bits bitmap. This is in the hot path so I'd like to see how I can speed things up. Right now I'm maintaining a header entry to know ...
1
vote
2answers
142 views

Line intersection detection algorithm

I'm trying to detect if a line drawn by the user intersects itself. I'm using a line intersection detection algorithm that goes through each waypoint of the line and checks if intersects with any ...
1
vote
2answers
73 views

Reading Element Names vs Reading Element Attributes: Speed C#

I am working on a project where there are a whole bunch of strings being stored in an XML file for later retrieval. Stored with each string is between 0-10 tags that a user can use to access and sort ...
7
votes
9answers
444 views

How often is software speed evident in the eyes of customers?

In theory, customers should be able to feel the software performance improvements from first-hand experience. In practice, sometimes the improvements are not noticible enough, such that in order to ...
8
votes
2answers
511 views

Is there any better approach to shortest path finding within a (vehicular) traffic network?

Dear fellow programmers, We're developing software which simulates vehicular traffic. Part of the process called "assignment" is concerned with assigning vehicles to their routes and has to use some ...
1
vote
1answer
93 views

How to evaluate the performance of a Data Access Layer b/w two ORM's?

I am currently working on a project where I am going to replace the Data Access Layer from a custom ORM to Entity Framework.(The product is almost complete and mostly any changes that will follow ...
2
votes
1answer
107 views

What happens when one reaches their framework's maximum requests per second?

I've been dabbling in code for many years now but it's always been personal projects. I don't have experience with much traffic. I was recently reading through a "Hello, World." tutorial for ...
2
votes
1answer
69 views

Is storing data directly in a list node better than storing a pointer to data?

Suppose we have two different doubly-linked list structures: One has content of the node embedded directly in the node: struct Content { // some stuff }; struct Node { struct Node *next; ...
0
votes
1answer
37 views

Tags DB structure - tags table using one join and GROUP BY, or pivot (join) table using two joins?

I'm implementing tags into my question and answer application. Users will be limited to the tags available by the app, so they can't choose their own. So maybe only 30-50 tags will be available. This ...
3
votes
1answer
204 views

Object caching in this code too expensive?

I'm having some trouble with a game developed in Java which is kinda slow. I benchmarked it a little bit and found the problem: most of the time, the JVM is in the Object.<init>() since there ...
2
votes
2answers
147 views

How to store data in memory(RAM) using php without using Memcache/Redis or any other software? [closed]

I want to implement a cache system in PHP consisting of following features 1) It should be able to store any(large or small) amount of data as long as the memory serves.(key value pair i.e. get & ...
0
votes
1answer
135 views

Lucene vs Solr - Indexing pdf/word documents reisiding on a NAS drive using .Net [closed]

Using ASP.Net, I want to implement full text search using Lucene/Solr on a LARGE number of docs (word, pdf etc.) residing in a directory on a NAS drive. The NAS drive would be mapped as a network ...
14
votes
3answers
2k views

why is the latter function 10% faster although it must create the variables over and over again?

var toSizeString = (function() { var KB = 1024.0, MB = 1024 * KB, GB = 1024 * MB; return function(size) { var gbSize = size / GB, gbMod = size % GB, mbSize = gbMod ...
0
votes
0answers
67 views

Writing Z80 table based assembler/disassembler

I have a long-term project: DIY computer with various processors. One of my wishes not only make hardware, but software too. So I started from assembler/disassembler for Linux, though there is a lot ...
0
votes
2answers
445 views

Mobile App Development-Architecture/Platform: Main performance concern: device/UI responsiveness [closed]

I am currently investigating different alternatives for building a mobile instant messaging application for iOS and Android, using an XMPP server (probably ejabberd) as the back-end. Main requirements ...
0
votes
1answer
37 views

Windows Firewall single rule with multiple IP addresses vs multiple rules with single IP address [closed]

I've tried finding some resources to help me on my dilemma, but wasn't successful in my approach. So here goes: I am implementing an automated firewall manager for Windows Firewall which will ban ...
90
votes
11answers
24k views

What backs up the claim that C++ can be faster than a JVM or CLR with JIT? [closed]

A reoccurring theme on SE I've noticed in many questions is the ongoing argument that C++ is faster and/or more efficient than higher level languages like Java. The counter-argument is that modern JVM ...
-3
votes
2answers
164 views

Can a high level language be faster than native C? [closed]

Hand-crafted C is almost unbeatable. If an experienced C developer knows what he is doing, he will be able to write C code much faster than higher level code. But can a medium/big programme written in ...
19
votes
5answers
5k views

Are DDD Aggregates really a good idea in a Web Application?

I'm diving in to Domain Driven Design and some of the concepts i'm coming across make a lot of sense on the surface, but when I think about them more I have to wonder if that's really a good idea. ...
1
vote
2answers
162 views

Should I prefer Python generators to lists?

Python iterators can be very memory efficient. Should I always prefer to use generators instead of just lists? In what situations should I prefer a plain array? For example instead of this: emails = ...
5
votes
2answers
542 views

Where is the evidence for the performance of Node.js?

A lot of developers, especially ones who haven't used Node.js in production, seem to believe that Node.js is faster than other interpreted languages such as PHP, Python, and Ruby. These claims ...
4
votes
1answer
152 views

Designing a better performing total permissions setup for multiple permission levels

We've got a global system that we are attempting to solve a permissions issue around. Currently, our system serves a number of different applications out to our clients and each client has their own ...
7
votes
2answers
491 views

How to efficiently store big time series data?

I need to store and to be able to query some very large amounts time series data. Properties of the data are as follows: number of series : around 12.000 (twelve thousand) number of data points, ...
1
vote
0answers
51 views

Reading large files for ETL program POC

I'm looking for some information on how to increase the performance of reading large text files for use in an ETL process. We're currently using a proprietary program that is more of a scripting ...
57
votes
7answers
10k views

Is a 1 < 10 comparison less expensive than 1 < 1000000?

I just used ~1 billion as the count for a z-index in CSS, and was thinking about the comparisons that must go on. Is there a difference in performance on the ALU level in comparisons between very ...
3
votes
2answers
220 views

Best practice for uploading large file, previewing, and editing before saving to database?

I am allowing users to upload a relatively large .csv file (about 1MB) - it will contain thousands of records that each represent one of my business objects. I want the users to upload the file and ...
1
vote
4answers
133 views

What do polynomial algorithms entail?

From here, I know it is that an algorithm that... ...is said to be solvable in polynomial time if the number of steps required to complete the algorithm for a given input is O(n^k) for some ...
11
votes
7answers
18k 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 ...
130
votes
13answers
31k views

Should we avoid object creation in Java?

I was told by a colleague that in Java object creation is the most expensive operation you could perform. So I can only conclude to create as few objects as possible. This seems somewhat to defeat ...
1
vote
2answers
140 views

Is it better to perform a calculation in the field's setter or have a different method?

I'm implementing a simple Quota object which determines a usage percentage based on the maximum and the used. private int maximum; private int used; public Quota(int used, int maximum) { ...
1
vote
2answers
123 views

Is it a Good Practice to Catch All Exception? [duplicate]

The snippet below (in java) gives an example of my question. try { // code implementation here } } catch (Exception ex) { } ...
0
votes
2answers
128 views

Periodically polling an API, are there alternatives?

I'm currently working on a service that is supposed to aggregate data from a number of APIs, unify the data, and offer it through another API to the users. I had a couple of ideas for solving this, ...
2
votes
3answers
168 views

Effect of denormalizing

Here's a scenario where I'm wondering whether to denormalize a relational database (MS SQL). Text description of the requirement I have users (stored in a users table). Users belong to Accounts: ...