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What is a “cache-friendly” code?
...her end of the memory spectrum (DRAM), the memory is very cheap (i.e. literally millions of times cheaper) but takes hundreds of cycles after a request to receive the data. To bridge this gap between super fast and expensive and super slow and cheap are the cache memories, named L1, L2, L3 in decre...
The performance impact of using instanceof in Java
...y heavy use of the instanceof operator. While I know that OO design generally tries to avoid using instanceof , that is a different story and this question is purely related to performance. I was wondering if there is any performance impact? Is is just as fast as == ?
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How are 3D games so efficient? [closed]
...dware.
For instance, one easy optimization you can make involves not actually trying to draw things that can't be seen. Consider a complex scene like a cityscape from Grand Theft Auto IV. The renderer isn't actually rendering all of the buildings and structures. Instead, it's rendering only what t...
ActiveRecord: List columns in table from console
...
Great! Using Model.columns provides all the information for a table through ActiveRecord. Crucially for me it was the only and easiest way to gain confidence in what my primary key really was at the database level.
– nibbex
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how do I work around log4net keeping changing publickeytoken
...em with the other answers are that they are using the same dll version for all bindings. I want to use features in the new version for everything else but the legacy dependency.
To be able to do that you need to do the following:
Start by downloading the old version (version of 1.2.11.0).
Rename...
Apache and Node.js on the Same Server
... the ProxyPass directive in the Apache httpd.conf its not too hard to pipe all requests on a particular URL to your Node.JS application.
ProxyPass /node http://localhost:8000
Also, make sure the following lines are NOT commented out so you get the right proxy and submodule to reroute http request...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...T(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) fo...
Check if table exists and if it doesn't exist, create it in SQL Server 2008
...read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects
vs. sys.tables. Basic form:
IF object_id('MyTable') is not null
PRINT 'Present!'
ELSE
PRINT 'Not accounted for'
Of course this will show as "Present" if there is any object present with that name. If yo...
Caveats of select/poll vs. epoll reactors in Twisted
...ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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Clone() vs Copy constructor- which is recommended in java [duplicate]
...rclass since the
Beta-release days of the Java
compiler*; and it, like all ancient
magic, requires the appropriate
incantation to prevent the spell from
unexpectedly backfiring
Prefer a method that copies the object
Foo copyFoo (Foo foo){
Foo f = new Foo();
//for all properties in F...