Does importing a large number of namespaces have an impact on performance? Specifically in C# .NET or in general? Obviously I would not import a namespace I wasn't going to use, and i'd probably never have to import so many as to worry about performance, but this is more out of general interest than an actual, practical problem i'm fa...
In analysing the performance of a JSF2 (Mojara) page returning 200 tabular rows I'm seeing 50% of the time taken to respond being in just rendering. For the 4 seconds on a dev box, 2 are purely down to the rendering of this page. What is the best path to improve performance? (I've been told to replace ui:repeat with jstl code?) Due t...
The title sums my question up pretty well: are there any open source OpenGL profilers for Linux? The only thing I could find was gDEBugger, but it only comes with a 7 day trial and is very much closed source. I would use this for free (as in freedom) software development so paying is not an option, though I might consider accept answers...
This has probably been asked over and over but I couldn't find anything useful so here it goes again... In my application I need to render a fairly large mesh (a couple of million triangles or more) and I'm having some problems getting decent frame rates out of it. The CPU is pretty much idling so I'm definitely GPU-bound. Changing the ...
Spring MVC 3.0 with Annotation seems like a great framework for the enterprise web development. However, the issue of performance tuning often comes up when you deal with any web applications, and I am wondering how the use of Annotations affects the strategy for improving performance. For example, would the Annotation-based validations ...
I have a quite big application, running from inside spree extension. Now the issue is, all requests are very slow even locally. I am getting messages like 'Waiting for localhost" or "waiting for server" in my browser status bar for 3 - 4 seconds for each request issued, before it starts execution. I can see execution time logged in log f...
Hello, I have a query which can be expressed 2 different ways with the same results. Which one is better - for performance or other reasons? First query: SELECT post_id FROM posts WHERE post_date BETWEEN '2010-01-01 00:00:00' AND '2010-12-31 23:59:59' Second query: SELECT post_id FROM posts WHERE YEAR(post_date)=2010 Tha...
I need to load over 1 billion keys into Berkley DB and therefore I want to tune it in advance to get better performance. With standard configuration it takes me now about 15min to load 1'000'000 keys which is too slow. Is there a proper way to tune for example the B+Tree of Berkley DB (node size etc...)? (As an comparision, after tuning...
I´ve a line of code that is called millions of times inside a for loop, checking if a passed argument is double.NaN. I´ve profiled my application and one of the bottlenecks is this simple function: public void DoSomething(double[] args) { for(int i = 0; i < args.Length;i++) { if(double.IsNan(args[i])) { //...
hello, i just profiled my reporting application when i tried to generate four times the same report in a row. the first one took 1859ms whereas the following ones only took between 400 and 600ms. what is the explanation for that? could i somehow use it to make my application faster? the reporting module runs on the server and waits for t...
I have a peak of CAL type interrupts, 20,000 per second. How do I find the process that's generating them on SUSE11? Thanks! ...
I need to display lots of rows in a grid added at a pretty high frequency (up to 10 rows per second in some cases) I chose ListView because I assume is the fastest grid control in WPF. (certainly a lot faster than GridView) CPU utilization gets pretty high after couple hundred thousand items were added and they continue to come in. This...
I have a class called "simulation" and a method for solving simulation. class sim { void Step() { } other methods (20+)... } Sim class is only instantiated once during the program. Step method is called in the order of millions during the program. Step method uses a lot of local variables (100+). None of those local...
We have a slow query that has a low optimizer_cost value but a very high user_io_wait_time value. Does this just indicate that there is an I/O bottleneck? Should we allocate more memory to Oracle? Get faster disks? Note: the stats were gathered by querying V$SQL ...
Question to SQLite database engine. I have fairly complex question, which finds path in directed graph between two sets of known nodes, with exactly one node between (to be precise, path in public transport routes, but it has graph representation). Now something unexpected - there are no explicit JOINs in question (only conditions in WH...
I have a L2S query with several joins that should returns 11 records in about 3 seconds. However, it times out after 30 seconds unless I specify a Take parameter (i used Take(20) even though it only returns 11 records) in which case it returns in the expected time frame of 3 seconds with the 11 records. The query looks like this: (fro...
Hi folks, I have (what I think) is a simple Sql Server spatial query: Grab all the USA States that exist inside some 4 sided polygon (ie. the viewport/bounding box of a web page's google/bing map) SELECT CAST(2 AS TINYINT) AS LocationType, a.Name AS FullName, StateId, a.Name, Boundary.STAsText() AS Boundary, CentrePoint.STAsT...
Chasing down some DB performance issues in a fairly typical EclipseLink/JPA application. I am seeing frequent queries that are taking 25-100ms. These are simple queries, just selecting all columns from a table where its primary key is equal to a value. They shouldn't be slow. I'm looking at the query time in the postgres log, using the...
Hello, thanks for your attention and time. I want to test asp.net application for stress, load and performance. Please guide me what free tools should be used for this ? Is there any tool which particularly can be used to analyse individual components, functions and scripts and resources they use ? Thanks in anticipation for your help...
After finishing school in Computer Science and entering the "real world" as a software engineer working on web applications, I've become overwhelmed by the amount of information to be learned about scaling web applications properly. Some topics/questions that have recently popped up for me: RDBMS's vs. unstructured data storage. Advant...