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

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0
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2answers
402 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
2answers
52 views

Control CPU Clock Speed with Software

I am currently working on various performance analysis of algorithms. For this purpose I am for now using my MacbookPro. It completely fulfills my needs as the 4 cores (8 possible threads) also let me ...
0
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1answer
21 views

Windows Firewall single rule with multiple IP addresses vs multiple rules with single IP address

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 ...
0
votes
1answer
90 views

How specific is too specific with css selectors?

The way that I like to write scss gives way to very specific selectors (code sample is under). Is this a bad thing? Are there any performance or reusability issues that I should consider? ...
1
vote
1answer
313 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 ...
89
votes
11answers
23k 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
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2answers
129 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 ...
18
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
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2answers
148 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 = ...
2
votes
1answer
163 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 ...
3
votes
0answers
370 views

Why is an inline if/else faster than a .get() in Python? [migrated]

I was reviewing some code earlier and the developer wrote an inline if/else rather than a get() to retrieve an element from a list if it exists (otherwise give it a default value). I decided to spring ...
0
votes
0answers
39 views

How to profile and compare two client-side approaches? [closed]

I'm facing a project in which presumably large datasets will be interactively visualized client-side. These datasets' sizes vary, both in number of rows and number of columns. The visualizations and ...
5
votes
2answers
450 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
142 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
217 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, ...
0
votes
0answers
38 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 ...
56
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
109 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
131 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
15k 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 ...
122
votes
13answers
28k 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
130 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
112 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
106 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
164 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: ...
1
vote
2answers
56 views

Should benchmarks (to compare processors performance) be compiled with optimization CFLAGS?

I need to compare performance of 2 processors and I concluded I should benchmark then with several various tests. I'm currently using linpack (HPL) (because it's still well known and used for ...
0
votes
1answer
43 views

Quickly write log entries from http requests in a MySQL database with high performance

When a dataset is saved in the software I use, a http request is triggered (fire-and-forget). Information like the timestamp, the user and the changes made are listed in the GET parameters. Now I ...
2
votes
3answers
88 views

Architecture for an event admission ticket scanner for events with multiple entries

I am working on a service that lets event organizers sell tickets to their events online (a lot like Eventbrite to be honest). The customers then print the tickets themselves (each ticket has a ...
2
votes
1answer
38 views

Solutions To Partial ORM Retrieval

I have read the following question regarding whether it is best to use objects with fully or partially populated data members. The 3 suggestions were: that perhaps using a fully populated ORM model ...
0
votes
1answer
156 views

What'd be better? To add one more local variable, or to call a method twice in general case?

I have the method which returns java.util.Date inside the hibernate-entity class: package ua.com.winforce.loto_partner.commons.db.entity; @Entity @Table(schema = "pr", name = "publice") public class ...
0
votes
1answer
63 views

Reflection performance in this iteration of a (probably) large excel file

I'm wondering the performance of reflection in this situation. I'm iterating a (probably) large excel file (let's say 3000 max) which it's going to be done from time to time, and the implementation ...
1
vote
1answer
238 views

In C#, performance wise, an object's size does matter when you access one of its members through a reference?

It may be a stupid question but in C#, performance wise, an object's size or complexity does matter when you access one of its members through a reference? Or only that specific member is all that ...
8
votes
4answers
315 views

Maintenance cost of SIMD programming code base

Question: The software industry's consensus is that clean and simple code is fundamental to the long-term viability of the code base and the organization that owns it. These properties lead to lower ...
6
votes
1answer
235 views

Log to file or to database table?

I'm developing a web application which uses MS SQL for various data: including users, user accounts, user licenses, license prices, invoices. I need to log users' real-time usage of the system, and ...
1
vote
2answers
186 views

How does Yahoo's Smush.It work and why doesn't everyone use it?

I've recently come across an application by Yahoo called SmushIt. Apparently it does lossless compression on images. Sometimes the image size is reduced by as much as 90%. This of course has major ...
9
votes
5answers
3k views

Is try-finally expensive

In case of code where you have to do a resource cleanup before exiting a function, is there a major performance difference between these 2 ways of doing it. Cleaning the resource before every return ...
5
votes
2answers
2k 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 ...
0
votes
3answers
610 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[] ...
1
vote
2answers
241 views

Most Efficient way to Compute the sum of divisors of N (1 ≤ N ≤ 1 000 000 000)

I want to write a code which computes the sum of divisors of a number N(1 ≤ N ≤ 1 000 000 000), excluding the number itself. However, I need an efficient way to do it. It suppose to print the answer ...
3
votes
1answer
105 views

Is console logging inappropriate for chatty applications?

12 Factor states that applications should log to the console, those console logs should should be unbuffered, and the logs should be redirected to someplace useful (file, database, whatever). But ...
1
vote
7answers
9k views

Merge sort versus quick sort performance

I have implemented merge sort and quick sort using C (GCC 4.4.3 on Ubuntu 10.04 running on a 4 GB RAM laptop with an Intel DUO CPU at 2GHz) and I wanted to compare the performance of the two ...
2
votes
2answers
130 views

Combine union with distinct

Situation: I need distinct results from two tables, that both have duplicates. I would like to know if I should combine UNION and DISTINCT. Example 1 - Only use distinct SELECT DistinctValue FROM ...
-1
votes
2answers
145 views

Does code format affect performance?

I think I have came across a few times when I reformat some segment of code, it performed the way I wanted it to other than the other poorly formatted segment of code? Does code format affect ...
0
votes
1answer
43 views

Balancing between performance, convenience & separation

Consider a web application that works with somewhat sensitive data on reliable, high performance clients. The data needs to be processed and manipulated. So far I have learned that when possible, ...
12
votes
8answers
395 views

500 databases or 1 database with 500 tables or just 1 table with all the records? [duplicate]

I currently have an application that is used by a single end customer. For ease of discussion assume the application only needs a single database table for all records. I now need to support ...
3
votes
1answer
74 views

Filesystem superblocks and their backup copies

I'd like to understand how (modern) filesystems are implemented and having trouble to fully understand superblocks and their backups. I reference ext4 and btrfs, but the questions may also apply to ...
5
votes
2answers
484 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 ...
4
votes
1answer
470 views

avoiding multiple calls to SQL while being modular

I have a BusinessLayer.dll which calls DataAccessLayer.dll which ultimately makes the tcp connection to the SQL server. Each business layer method has a corresponding method in the data access layer ...
3
votes
1answer
540 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 ...
13
votes
6answers
8k views

Is there any reason to use varchar over text columns in a database?

Is varchar just a remnant from before text came around, or are there use cases where you would want to use a varchar? (Or char for that matter..) (I use Postgres and MySQL (MyISAM) daily, so those ...