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

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-3
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0answers
45 views

Efficient programming: Java [on hold]

I have just started to learn Java, this is my first programming language. I would like focus on efficiency from the beginning to be able to write fast programs. What is the basic "know-how" related ...
0
votes
0answers
25 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
75 views

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

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 ...
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 ...
6
votes
2answers
313 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 ...
0
votes
1answer
55 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 ...
1
vote
2answers
80 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 ...
1
vote
1answer
93 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
64 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 ...
5
votes
1answer
237 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 ...
3
votes
5answers
170 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
87 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
0answers
55 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 ...
3
votes
1answer
286 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 ...
4
votes
1answer
236 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) { ...
2
votes
0answers
50 views

Argument over performance using Convert.ChangeType in Web Applications [duplicate]

A debate has been going on at work about using Convert.ChangeType. A couple of fundamental assumptions to this discussion are delineated below: 1. The discussion is within the context of web ...
4
votes
1answer
248 views

How does modulus work?

I am not asking asking how the mathematical concept of modulus works, or how 20 % 3 == 2 I understand this fine. I'm more curious how the compiler/interpreter determines this. I can think of a very ...
5
votes
2answers
112 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
507 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
235 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 ...
1
vote
4answers
196 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 ...
2
votes
3answers
214 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
1answer
165 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 ...
0
votes
3answers
101 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 ...
1
vote
1answer
151 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 ...
1
vote
1answer
60 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
245 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 ...
14
votes
1answer
944 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 ...
1
vote
2answers
123 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 ...
1
vote
1answer
103 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
129 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 ...
15
votes
2answers
398 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 ...
2
votes
2answers
94 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
63 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 ...
2
votes
2answers
260 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
213 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 ...
2
votes
2answers
90 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 ...
0
votes
0answers
110 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 ...
3
votes
1answer
133 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
154 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 ...
0
votes
1answer
53 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 ...
-3
votes
2answers
195 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 ...
1
vote
2answers
169 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
636 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 ...
1
vote
0answers
68 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 ...
3
votes
2answers
309 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
138 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 ...
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 ...
1
vote
2answers
150 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) { ...