Hi, We are developing a client-server desktop application(winforms with sql server 2008, using LINQ-SQL).We are now finding many issues related to performance.These relate to querying too much data with LINQ , bad database design,not much caching etc.What do you suggest,we should do - how to go about solving these performance issues? On...
Hi; Is it possible to disable session handling in Joomla 1.5 for guests. I donot use user system in the frontend, i assumed that it's not needed to run queries like below: Site will use APC or Memcache as caching system under heavy load, so it's important for me tHanks for your comments DELETE FROM jos_session WHERE ( time < '127470...
I am currently part of a team designing a site that will potentially have thousands of users who will be doing a number of date related searches. During the design phase we have been trying to determine which makes more sense for performance optimization. Should we store the datetime field as a mysql datetime. Or should be break it up i...
I have a page which displays ~300 pages worth of tabular data. Firefox, Chrome, Safari all work fine but IE 7, 8, and 8 Compatibility view all wretch. It lags for several seconds when I try to scroll or press the page up/page down button. Pagination, smaller data sets, and other usability suggestions will not work for this page. Assu...
I have a large scientific computing task that parallelizes very well with SMP, but at too fine grained a level to be easily parallelized via explicit message passing. I'd like to parallelize it across address spaces and physical machines. Is it feasible to create a scheduler that would parallelize already multithreaded code across mult...
Hello all, First of all I'm a newbie when it comes to Android programming. So if this question is totally stupid please delete it ASAP :-). Question: I'm going to draw a grid of 10x10 PNG images. Each image is 32x32 px. All of the images are unique. I'm thinking that the easiest way seems to be to put each image in an ImageView. If...
I have a table in MySQL with 7 indexes, most of them are on more than one column. I think here is too much indexes. Is there any way to get statistics of what indexes are used more by all thousands of queries to this database and what are less worthy so I know what index to consider to remove in first place? ...
I have 10mln rows in my table in MySQL and 7 indexes on this table. Now when I try to add 8th it takes infinite time to do this. Is there any way to workaround this problem to add easily and fast 8th index? ...
I have a performance issue where I suspect one standard C library function is taking too long and causing my entire system (suite of processes) to basically "hiccup". Sure enough if I comment out the library function call, the hiccup goes away. This prompted me to investigate what standard methods there are to prove this type of thing? W...
I just started using the chrome developer tools for some basic html websites and I used the audit tool. I had two identical images, one with the height and width attribute, and one without. On the Resources section, both the latency and the download time were identical. However, the Audit showed Specify image dimensions (1) A width an...
I would have assumed that GL_FIXED was faster, but the iPhone docs actually say to use GL_FLOAT because GL_FIXED has to be converted to GL_FLOAT. Is it the same on Android? I suppose it varies by phone, but what about recent popular ones (Nexus One, Droid/Milestone, etc.)? Bonus points: This appears to be completely undocumented (e.g. s...
I noticed in C#, unlike C++, you can combine virtual and generic methods. For example: using System.Diagnostics; class Base { public virtual void Concrete() {Debug.WriteLine("base concrete");} public virtual void Generic<T>() {Debug.WriteLine("base generic");} } class Derived : Base { public override void Concrete() {Debug...
I am currently looking at some JProfiler traces from our WebSphere-based application, and am noticing that a significant amount of CPU time is being spent in the class com.ibm.io.async.AsyncLibrary.getCompletionData2. I am guessing, but I am wondering whether this is PMI-related (and we do have this enabled). My knowledge of PMI is li...
My C# (.NET 2.0) application has a StringBuilder variable with a capacity of 2.5MB. Obviously, I do not want to copy such a large buffer to a larger buffer space every time it fills. By that point, there is so much data in the buffer anyways, removing the older data is a viable option. Can anyone see any obvious problems with how I'm ...
I need to develop a performance evaluator for piano playing. Based on a midi generated from sheet music, I need to evaluate the midi of the actual playing (midi keyboard). I'm planning to evaluate the playing based on note pitch, duration and loudness. The evaluation is I suppose a comparison of the notes of the sheet music and playing i...
While the site is in development mode, it takes for ever to edit content types and do various similar administrative tasks. Is there a way to speed this up? What kind of hardware would I need? Any specific MySQL optimization maybe? ...
Hi! I recently tried developing a small-sized project in C# and during the whole project our team used the Test-Driven-Development (TDD) technique (xunit, moq). I really think this was awesome, because (when paired with C#) this approach allowed to relax when coding, relax when projecting and relax when refactoring. I suspect that all ...
I understand that there are queries you can't express in LINQ to NHibernate that you can using NHibernate Criteria. But, as far performance, is it safe to assume that using NHibernate Criteria is generally better than LINQ to NHibernate? ...
I'm running a php/mysql-driven website with a lot of visits and I'm considering the possibility of caching result-sets in shared memory in order to reduce database load. However, right now MySQL's query cache is enabled and it seems to be doing a pretty good job since if I disable query caching, the use of CPU jumps to 100% immediately. ...
hello I am trying to use oprofile to generate call graph. Compiler is g++, platform is linux x86-64, linker is gfortran C++ code is compiled with -fno- omit-frame-pointer. oprofile is started with --callgraph=25. report I run with --callgraph. the call graph is produced but it's only includes self time, which is not much use what am ...