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

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3
votes
3answers
106 views

Do microservices scale down?

I've been reading up on microservices architecture, which gained a lot of recognition in recent years. As a big fan of UNIX philosophy, I find it very clean and sensible. However, exisiting ...
0
votes
1answer
36 views

PHP MVC concept large controller

I have custom MVC framework in PHP and my controller file has about 5000 lines. The question is, is it a big concept flaw? It is structured code with kiss method and quite maintainable. Are there ...
0
votes
1answer
71 views

Immutable class with behavior

I've just finished Effective Java and I loved it. I'm trying to refactor one of my programs to take advantage of what I've learned, and I have a lot of questions regarding immutability. My program is ...
13
votes
10answers
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 ...
2
votes
1answer
50 views

How do I handle long running third party calls from backing up my message queue?

Here is my exact scenario. I must make requests to a third party service The service takes ~15 seconds to respond It also has no webhooks or any call back mechanisms These requests are not made ...
21
votes
2answers
2k 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 ...
6
votes
1answer
705 views

Is event sourcing ready for prime time? [closed]

Event Sourcing was popularized by LMAX as a means to provide speed, performance scalability, transparent persistence and transparent live mirroring. Before being rebranded as Event Sourcing, this type ...
1
vote
0answers
34 views

Do I want an index if all I care to query is field not null [migrated]

In SQL, do all the common considerations about indexes apply if everything I'll ever want to query (in the where condition) is when a field is not null? Is there a special configuration of the index ...
2
votes
1answer
91 views

In C#, is it good practice to use implicit numeric conversions from int to float?

For example: if(5.0f > 1) { } Does it have a significant performance penalty? Compared to just doing if(5.0f > 1.0f) { }
8
votes
2answers
3k views

Why use Android Fragments?

I have read the documentation and some other questions' threads about this topic and I don't really feel convinced; I don't see clearly the limits of use of this technique. Fragments are now seen as ...
2
votes
3answers
267 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 ...
1
vote
2answers
85 views

Caching query results vs Querying each time (finding a middle ground)

This is kind of an expansion on a previously asked question Some background info: Querying Over 5,000 items from SQL database that eventually get sorted into a list depending on who the user ...
0
votes
0answers
33 views

BCMath vs MySQL: performance

Scenario I am working on a web application that handles financial transactions, and my code will need to be reusable for everything from consumer carts to manufacturer/distributor shipments. The ...
-3
votes
1answer
80 views

Java - Best way to set properties of an object [closed]

I don't know if there is any difference in performance, or its just a matter of choice, but I am a perfectionist like that, and I'd like to know. Lets say you have the object HolySheet. You can set ...
3
votes
4answers
1k views

Database is performing slow, even all the tables are having normalization

An interviewer asked me this question: Tables are created with appropriate normalization rules, However the database is performing slow. [Ie.: The select, insert statements are taking time to do ...
2
votes
4answers
2k views

Best resources to really understand run-time complexity [closed]

I'm familiar with the basics of run-time analysis such as what makes certain types of code O(n) and O(n^2). But I'm having real trouble learning, understanding, and really remembering how to analyze ...
2
votes
0answers
57 views

Truncating HTML content at specific content blocks

I have HTML content in my DB and I would like to present a list of these individual items but truncate each of them so they're not fully displayed. I would like to keep truncated items ...
7
votes
2answers
2k views

Does LINQ require significantly more processing cycles and memory than lower-level data iteration techniques?

Background I am recently in the process of enduring grueling tech interviews for positions that use the .NET stack, some of which include silly questions like this one, and some questions that are ...
17
votes
7answers
9k views

Why is NoSQL faster than SQL?

Recently I was asked: Why is NoSQL faster than SQL? I didn't agree with the premise of the question... it's just nonsense for me personally. I can't see any performance boost by using NoSQL ...
6
votes
2answers
321 views

How does the Hip hop virtual machine (HHVM) theoretically improve PHP runtime performance?

From a high level, how does Facebook, et. al use to improve PHP performance with the Hip Hop Virtual Machine? How does it differ from executing code using the traditional zend engine? Is it because ...
8
votes
3answers
1k views

What is the best way to keep track of the median?

I read a question, and I'm looking for input on how to solve it: Numbers are randomly generated and stored into an (expanding) array, How would you keep track of the median? There are two data ...
5
votes
1answer
261 views

Kth selection routine - Floyd Algorithm 489

I have recently come across a promising Kth selection routine that reportedly outperforms quickselect the Floyd, Rivest Select routine. This Wikipedia article provides a pseudocode version which I ...
0
votes
0answers
31 views

Where to generate View?

I plan to build a CRM for small companies. It is supposed to be a single-page application. Now I am unsure where it is more efficient to convert the data to HTML. Should I rather do it on the server ...
61
votes
15answers
14k 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/ ...
0
votes
1answer
60 views

How to handle rating? [closed]

I want to implement like/dislike system, but I don't know how to achieve best performance. I have to tables: blog posts and comments that need rating. Should I store all data in one rating table? Or ...
3
votes
5answers
226 views

Term for Performance Issues Due to Looping [closed]

Is there a term for performance issues caused by someone creates a loop that performs hundreds or thousands of actions that could have been done in bulk? My example is that I keep running into loops ...
3
votes
1answer
259 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 ...
15
votes
3answers
10k 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 ...
1
vote
1answer
47 views

Performance and data retrieving

I'm currently developing a mobile application in Objective C for iOS devices. While doing the application I reach the point where I have to retrieve data from a database and show it on a table (the ...
10
votes
9answers
884 views

Is it appropriate in a developer's job description to have “error free” as a key output? [closed]

As part of a review of all job descriptions, my company has decided to include the following as a key output: website development completed on time, within specification and error free Given ...
2
votes
4answers
415 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) ...
1
vote
1answer
97 views

When the result set doesn't matter should Left Join or Inner Join be used

When you have a query where you're joining from a non-null foreign key to the foreign table it doesn't matter if you use LEFT JOIN or INNER JOIN from a result standpoint (since there won't be any ...
2
votes
1answer
553 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 ...
2
votes
1answer
68 views

How do hybrid interpreter-JIT compilers work?

Chrome's V8 compiler, the Java HotSpot compiler, and many more have multiple tiers of interpretation and compilation. A function starts off as interpreted in HotSpot and then, if it is run often ...
4
votes
1answer
268 views

Is Collection.stream().filter().forEach() inefficient compared to a standard for each loop?

IntelliJ IDEA recommended to me just now to replace the following for-each loop with a Java 8 "forEach" call: for (Object o : objects) { if (o instanceof SomeObject) { ...
0
votes
3answers
110 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 ...
3
votes
5answers
189 views

Should I use BLOB or Tables for storing large data?

Problem Currently investigating a solution to improve the performance of a web application. The application works well for small projects, but faces performance issues in the UI when working with ...
-2
votes
1answer
91 views

Java - Concept question: LinkedHashMaps vs POJOs?

EDIT: I'm just going to ask a single question instead of presenting a problem and asking for advice on a specific design decision in the solution. Given a batch of data from a database, collected ...
2
votes
2answers
187 views

Will using multiple recordsets in one database request be more efficient?

I am redeveloping an old ecommerce website which is currently written in C# ASP.NET 2.0. Because this is a reasonably high volume website and has suffered performance issues I want to develop in the ...
2
votes
2answers
54 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 ...
12
votes
7answers
570 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 ...
2
votes
1answer
133 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 ...
122
votes
30answers
11k views

Is micro-optimisation important when coding?

I recently asked a question on Stack Overflow to find out why isset() was faster than strlen() in PHP. This raised questions around the importance of readable code and whether performance improvements ...
59
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
1answer
302 views

Why is iterating through List<T> more expensive than iterating through Array in .NET?

According to the answers in this post, List<T> is backed by an Array. According to this article, list iteration is considerably slower than array iteration. If Lists are arrays 'under the ...
5
votes
4answers
537 views

What are the reasons for great performance differences running the same program?

I wrote a Python program that has to perform some expensive spatial searches while holding lots of data in memory. I tried to improve the performance, that is tried different approaches (see my ...
1
vote
2answers
149 views

Reading Element Names vs Reading Element Attributes: Speed

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 are between 0-10 tags that a user can use to access and sort ...
25
votes
10answers
13k views

Why Should I Avoid Inline Scripting?

A knowledgeable friend recently looked at a website I helped launch, and commented something like "very cool site, shame about the inline scripting in the source code". I'm definitely in a position ...
4
votes
3answers
885 views

On access scans and Visual Studio

Where I work McAfee On Access scan is enforced to be on for all our machines. Visual Studio 2010 isn't exactly the speediest program at times but combining a large website, several build ...
2
votes
2answers
95 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; ...