Questions tagged [redundancy]
Redundancy is the duplication of critical components or functions of a system with the intention of increasing reliability of the system, usually in the case of a backup or fail-safe.
redundancy
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How to deploy an ASP.NET Application with zero downtime
To deploy a new version of our website we do the following:
Zip up the new code, and upload it to the server.
On the live server, delete all the live code from the IIS website directory.
Extract the ...
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Why do we have map, fmap and liftM?
map :: (a -> b) -> [a] -> [b]
fmap :: Functor f => (a -> b) -> f a -> f b
liftM :: Monad m => (a -> b) -> m a -> m b
Why do we have three different functions that ...
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How to check for duplicate CSS rules? [duplicate]
I messed up my css and somehow i have a lot of the duplicate rules and my 1800 something lines css file is now of 3000+ lines..
Is there any way/tool that would take my css file as input and check ...
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How To Check Dependencies Between Jar Files?
I recently have taken the support and programming of a web system written in JSF. The code is kind of messy and redundant, and yes, no documentation exists.
The system has over 40 jar libraries, and ...
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How to reduce boilerplate currently necessary for serialization
Our software is abstracting away hardware, and we have classes that represent this hardware's state and have lots of data members for all properties of that external hardware. We need to regularly ...
- 223k
19
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3
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Can CloudFlare perform automatic failover to a different backend?
I am looking for an easy way to fail over to a different DC quickly, does CloudFlare offer anything special in this regards with things like health checks or is it just like a standard DNS service?
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Pretty print expression with as few parentheses as possible?
My Question: What is the cleanest way to pretty print an expression without redundant parentheses?
I have the following representation of lambda expressions:
Term ::= Fun(String x, Term t)
| ...
- 418k
16
votes
5
answers
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Replication vs Redundancy
I am currently reading about Distributed Systems and I am facing two different terms which are described in a similar manner: Replication and Redundancy.
Can anyone explain each term in part?
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CSS "Normalizer" tool? [closed]
I need to maintain & improve an existing website and I am drowning in the redundancy I have discovered in its CSS stylesheet. Given the existing redundancy and non-methodlogical ordering of ...
- 14.9k
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Database normalization - who's right?
My professor (who claimed to have a firm understanding about systems development for many years) and I are arguing about the design of our database.
As an example:
My professor insists this design is ...
- 1,442
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Remove duplicated elements from list
I have a list of character vectors:
my.list <- list(e1 = c("a","b","c","k"),e2 = c("b","d","e"),e3 = c("t","d","g","a","f"))
And I'm looking for a function that for any character that appears ...
- 6,242
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Sessions Failover with PHP-memcache against memcached
Colleagues!
I'm running php 5.3 (5.3.8) with memcache (2.2.6) client library (http://pecl.php.net/package/memcache) to deal with memcached server.
My goal is to have failover solution for sessions ...
- 362
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1
answer
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small code redundancy within while-loops (doesn't feel clean)
So, in Python (though I think it can be applied to many languages), I find myself with something like this quite often:
the_input = raw_input("what to print?\n")
while the_input != "quit":
print ...
- 5,897
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Cross-colo fail-over design, DNS level fail-over?
I'm interested in cross-colo fail-over strategies for web applications, such that if the main site fails users seamlessly land at the fail-over site in another colo.
The application side of things ...
- 105k
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4
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How can I merge two redundant records in a MySQL table, maintaining all PK/FK relationships?
Say I have a table customers with the following fields and records:
id first_name last_name email phone
------------------------------------------------------------------------
...
- 1,172
9
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4
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programmatically optimizing expressions (by removing redundant computations)
I had a pretty big equation that I needed to use to solve for a given variable. So I used an online tool that was capable of rewriting an equation in terms of a given variable. It gave me some huge ...
- 5,897
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How can I reduce the redundancies in my jQuery code?
The size of my JavaScript file is getting out of hand because I have hundreds of links, and each one has its own jQuery function even though they all peform basically the same task.
Here's a short ...
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How to apply different layouts to the same target in NLog?
NLog allows me to use SplitGroup to log my messages to several targets. I'd like to use this feature to log each message to a common, user-specific and date-specific logs at once:
<variable name="...
- 267k
9
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1
answer
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Generalizing these lines of code?
While programming, I ran into a wall with some code. It looks like this:
And that's the problem. I took a pretty screenshot to reduce my guilt. The pretty colors do not make up for the lack of ...
- 9,030
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How to use fastcgi_next_upstream in Nginx [closed]
I'd like to have 1 web server (nginx) and 2 FastCGI instances of the same application as back-end. The idea is to forward requests to second one if the first one is down.
Apparently, I need to use ...
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Geo Redundancy in Azure Service Fabric Applications
I'm trying to come up with a solution for achieving Geo-Redundancy (2+ datacentres) while using Service Fabric reliable Actors/Services to manage state. It insinuates here that geo replication is ...
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How to make my Java application scalable and fault tolerant?
In a simplified manner my Java application can be described as follows:
It is a web application running on a Tomcat server with a SOAP interface. The application uses JPA/Hibernate to store data in ...
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cppcheck thinks I have "Redundant code: Found a statement that begins with numeric constant"
Cppcheck (version 1.46.1) gives the following warning for an enum like this one:
enum DATABASE_TYPE
{
DATABASE_TYPE_UNKNOWN = -1, // <- line of warning
DATABASE_TYPE_ORACLE,
...
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8
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Elasticsearch deployment in a 2 server load balanced node js application setting
I have the following production setup for my Node JS application:
I am now going to integrate Elasticsearch in this setup. My question is regarding the best practices for deploying Elasticsearch in ...
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Do you put a super() call a the beginning of your constructors?
This is a question about coding style and recommended practices:
As explained in the answers to the question unnecessary to put super() in constructor?, if you write a constructor for a class that is ...
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7
votes
1
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JQuery : Event on click or keydown without redundancies?
What is the best way to do the same action if either a key press or a click is registered ?
I would like to avoid having redundancies and make the code shorter.
Thank you
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Avoid Redundancy in Python
I recently started using Python 2.6 for Ubuntu Server admin and have two minor issues concerning redundancy:
First thing are imports: They all look something like
import Class from Class
from ...
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Node.js - Requiring mongoose here and there causes redundancy?
I have the following Node.js directory structure.
|--app/
|--app.js
|--routers/
|--index.js/
|--models/
|--schemas.js
|--post.js
In app.js, there's a line likes this ...
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Database replication for redundancy using a free database and a Java with Spring & Hibernate web application
I have this in mind:
On each server: (they all are set up identically)
A free database like MySQL or PostgreSQL.
Tomcat 6.x for hosting Servlet based Java applications
Hibernate 3.x as the ORM tool
...
user14070
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10
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How to use code from one class in another? (Java)
I'm making a tank game and to avoid redundancy I'm making classes to extend.
My MenuPanel looks like this atm
(I've only written the code that matters for the question)
(knop = dutch for button)
...
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How to manage version history for Many-To-Many relationship using deltas in Hibernate?
We are working on a system where a person can send a document to another person, a document can have multiple attachments, as given below.
Document {
Set<Attachment> attachments;
}
If X ...
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redundant encoding?
This is more of a computer science / information theory question than a straightforward programming one, so if anyone knows of a better site to post this, please let me know.
Let's say I have an N-...
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Full recovery data using reed solomon
I'm testing a Reed Solomon algorithm from this repository in order to recover info in case something is externally changed.
Assuming:
m = bits per symbol
k = data
r = redundance
n = bits per block ...
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5
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How do I avoid redundant data fields in the result set when using JOINs?
Following join is supposed to retrieve user info along with their messages for users with a certain status:
SELECT * FROM user, message WHERE message.user_id=user.id AND user.status=1
The problem is ...
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C# Designer: Removing redundant code from Design.cs
I have a form which has several buttons, labels and other stuff on it, but the designer appears to remember old elements of that form that have previously be deleted.
Is there anyway to 'refresh' the ...
MeeMMeeM
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3
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Redundancy, reliability and fault tolerance in C# - where to look for examples?
I want to learn how to create truly robust applications in .net - ones that are fault tolerant and are capable of withstanding unexpected situations. Where can I find literature/guidance on this ...
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How to estimate a QR code redunduncy level?
I'm not a specialist, but as far as I know, a bit of information in a QR-code is coded more than once, and it is defined as the redundancy level
How can I estimate a QR-code redundancy level ? Is ...
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Should I opt for code repetition or consolidation with api service - JS
I'm working on a large CMS system where a particular module and its submodules take advantage of the same backend API. The endpoint is exactly the same for each submodule aside from its "document ...
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Creating Redundancy for a Subversion Repository?
What is the best way to create redundant subversion repositories?
I have a subversion repository (linked through apache2 and WebDAV) and would like to create a mirror repository on a different server ...
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Vowpal Wabbit Interaction Redundancy
I am curious about the way VW appears to create interaction terms, through the -q parameter.
For the purpose of this illustration I am using this toy data, which is called cats.vm:
1 |a black |b ...
- 1,810
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Change Azure Backup Vault Redundancy
We use Azure Backup and set our backup vaults to use GRS. We want to use LRS instead. It is understood that this cannot be changed once machines have been added to the vault, and we need to start from ...
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Redundancy Amazon S3 / Rails
We use amazon S3 buckets for publishing js files and putting them on client web sites. In other words, js files are stored in amazon s3. The main problem is since these files are on client sites, we ...
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How best to split a file into N parts with M redundant parts such that any N of the N+M parts is sufficient to reconstuct it?
Looking for the best algorithm to take a file, split it into N parts, add M redundancy parts and then store the file in N+M different locations. Files would typically be large.
For example: a 1GB ...
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How does enterprise failover, such as with google.com, actually work? [closed]
We have a few fedora systems that are configured for web, FTP, and email services. We'd like to mirror these services, so that we can provide near 100% reliability for our users. I'm a fairly ...
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Error correcting code
For a payment system that allows bank/wire transfers, I need to reliably associate payments with the corresponding user account that they are intended for. For this, the user should include a ...
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Can i use Google Apps as a fail-over mailserver?
I have my own exchange for emails. There are times when my exchange service is down (because of power failure or maintanance) and during this time, my users do not have access to the exchange web ...
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Including sparql sub-queries from separate files
Complex SPARQL queries are laborious to construct, and are difficult to read. Is there is way to `include' sub-queries in SPARQL, such as using an "include queryX" line, that would save one from ...
- 1,832
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I need to store HTML emails in a database. Is that a bad idea?
The templates for these HTML emails are all the same, but there are just different variables for say, first name, last name and such.
Would it just make sense to store the most minimal of data that I ...
- 186k
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Comparing similar strings in jquery
How do I compare similar strings in jquery?
<script src="../../js/jq.js"></script>
<script>
$(function(){
var str1 = $.trim($('#str1').val().toUpperCase());
var str2 = $....
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Is it bad to use two CDNs for a Javascript library?
A client's website was depending on the jquerytools.org CDN, which is currently not working and therefore his site is broken (disregarding graceful Javascript degradation). He could host the relevant ...
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