Hi, I am doing some Java performance comparison between my classes, and wondering if there is some sort of Java Performance Framework to make writing performance measurement code easier? I.e, what I am doing now is trying to measure what effect does it have having a method as "synchronized" as in PseudoRandomUsingSynch.nextInt() compar...
Hi, I have heard from many people that usage of templates make the code slow. Is it really true. I'm currently building a library. There are places where if templates are not created, it would result in code management problem. As of now I can think two solutions to this problem: use #defines Use templates and define all possible t...
What is the best way to handle mysql database users connection in PHP? I have a web server running a PHP application on MySQL. I have created a database user for the application: dbuser1 with limited access - only for query, insert and update tables. No alter table. Now the question is, should i use the same dbuser1 widely in my script...
I've been wondering if using long descriptive variable names in WinForms C# matters for performance? I'm asking this question since in AutoIt v3 (interpreted language) it was brought up that having variables with short names like aa instead of veryLongVariableName is much much faster (when program is bigger then 5 liner). I'm wondering i...
Is there a way to see how many context switches each thread generates? (both in and out if possible) Either in X/s, or to let it run and give aggregated data after some time. (either on linux or on windows) I have found only tools that give aggregated context-switching number for whole os or per process. My program makes many context s...
I have a database that won't grow much in size. It's current size is about 1 GB. Achieving the fastest performance is desired. Question: When should I use Memcache vs simply using MySQL Innodb ability to store all my content within RAM (innodb_buffer_pool_size)? ...
I've noticed major music festivals (at least in Australia) and other events that experience a peak in traffic when tickets go on sale have huge problems keeping their websites running well. I've seen a few different techniques used to try combat this such as short sessions and virtual queues but they dont seem to have much effect. If yo...
for tables with > 1,000,000 rows and possibly many many more ! haven't done any benchmarking myself so wanted to get the experts opinion. Looked at some articles on row_number() but it seems to have performance implications What are the other choices/alternatives ? ...
I am looking for a time efficient method to parse a list of files into a tree. There can be hundreds of millions of file paths. The brute force solution would be to split each path on occurrence of a directory separator, and traverse the tree adding in directory and file entries by doing string comparisons but this would be exceptionall...
Hello. I am working for an intranet application. Therefore I have some control on the client machines. The JavaScript library I am using is somewhat big in size. I would like to pre-install OR pre-load OR cache the JavaScript library on each machine (each browser as well) so that it does not travel for each request. I know that browsers ...
I'm inserting a batch of 100 records, each containing a dictonary containing arbitrarily long HTML strings, and by god, it's slow. On the iphone, the runloop is blocking for several seconds during this transaction. Is my only recourse to use another thread? I'm already using several for acquiring data from HTTP servers, and the sqlite do...
Hi. I've encountered in the following paragraph: “Debug vs Release setting in the IDE when you compile your code in Visual Studio makes almost no difference to performance… the generated code is almost the same. The C# compiler doesn’t really do any optimisation. The C# compiler just spits out IL… and at the runtime it’s the JITer that...
i'm using enums to replace String constants in my java app (jre 1.5). is there a performance hit when i treat the enum as a static array of names, in a method that is called constatnly (e.g. when rendering the UI)? my code looks a bit like this: public String getValue(int col) { return ColumnValues.values()[col].toString(); } than...
I am using eclipse , when I use shortcut to generate override implementations , there is an override annotation up there , I am using JDK 6 , this is all right , but under JDK 5 this annotation will cause an error, so I want to ask , if this annotation is completely useless ? Will compiler do some kind of optimization using this annotati...
I am currently evaluating named pipes for IPC on Windows with .NET/C#. I am currently looking at a single producer, single consumer scenario. Are there any good performance consideration guidelines? In my first test case I was comparing the speed of large messages vs small messages and seems to be that large (64k) messages are sent as qu...
Hi I was investigating the performance hit of creating Cachedependency objects, so I wrote a very simple test program as follows: using System; using System.Collections.Generic; using System.Diagnostics; using System.Web.Caching; namespace Test { internal class Program { private static readonly string[] keys = new[] {"A...
Hi I have a need for a counter of type long with the following requirements/facts: Incrementing the counter should take as little time as possible. The counter will only be written to by one thread. Reading from the counter will be done in another thread. The counter will be incremented regularly (as much as a few thousand times per s...
I am currently writing my truly first PHP Application and i would like to know how to project/design/implement MySQL Views properly; In my particular case User data is spread across several tables (as a consequence of Database Normalization) and i was thinking to use a View to group data into one large table: CREATE VIEW `Users_Merged`...
I encountered a strange problem where increasing my occupancy by increasing the number of threads reduced performance. I created the following program to illustrate the problem: #include <stdio.h> #include <stdlib.h> #include <cuda_runtime.h> #include <cutil.h> __global__ void less_threads(float * d_out) { int num_inliers; for...
When i was reading books to learn C# (might be some old Visual Studio 2005 books) I've encountered advice to always use SqlCommand.Prepare everytime I execute SQL call (whether its' a SELECT/UPDATE or INSERT on SQL SERVER 2005/2008) and I pass parameters to it. But is it really so? Should it be done every time? Or just sometimes? Doe...