performance

Is there any tool like New Relic RPM that integrates with ASP.NET?

I am intruiged by RPM's ability to profile a live, production site - analyzing performance under real-life load, etc. Thanks! ...

C: using a lot of structs can make a program slow?

I am coding a breakout clone. I had one version in which I only had one level deep of structures. This version runs at 70 fps. For more clarity in the code I decided the code should have more abstractions and created more structs. Most of the times I have two two three level deep of structures. This version runs at 30 fps. Since there ...

Minimizing Java Thread Context Switching Overhead

I have a Java application running on Sun 1.6 32-bit VM/Solaris 10 (x86)/Nahelem 8-core(2 threads per core). A specific usecase in the application is to respond to some external message. In my performance test environment, when I prepare and send the response in the same thread that receives the external input, I get about 50 us advanta...

SQL Server 2005 FREETEXT() Perfomance Issue

I have a query with about 6-7 joined tables and a FREETEXT() predicate on 6 columns of the base table in the where. Now, this query worked fine (in under 2 seconds) for the last year and practically remained unchanged (i tried old versions and the problem persists) So today, all of a sudden, the same query takes around 1-1.5 minutes. ...

How can I disable Java garbage collector ?

Hi, we have a PHP webapp that calls a java binary to produce a pdf report (with jasperreport), the java binary outpus pdf to standart output and exits, the php then send the pdf to browser. This java command lasts about 3 to 6 seconds, I think when it lasts 6 second it's because the GC kicks in, so I would like to disable it because anyw...

What happens before applicationDidFinishLaunching is invoked?

I'm doing performance testing on my iphone app and I'm noticing that sometimes a good 3-4 secs elapse at startup before I start seeing my NSLogs from applicationDidFinishLaunching. I've optimized what happens once the code enters applicationDidFinishLaunching but I'm not sure how to optimize what goes on before that. I'm using a Defaul...

Possibility of a custom Contacts field with a set list of values and Contacts lookup performance

I'm pretty sure it's not viable to do what I'd like to based on some initial research, but I figured it couldn't hurt to ask the community of experts here in case someone knows a way. I'd like to create a custom field for contacts that the user is able to edit from the main Contacts app; however, the user should only be allowed to selec...

Objective-C and Protocols

Do protocols come with any overhead? (ie. obvious benefits aside, do they slow things down?) ...

reasons why GcTimeLimit might not be erroring out?

I have a web service in Java, contained in Jetty. I'm using Sun's Java 6 with the default ParallelGC, and I have the following command-line options turned on: "-verbose:gc -XX:+PrintGCTimeStamps --XX:+PrintGCDetails". When my process is out of memory, I see loglines like this, back-to-back: 66872.846: [Full GC [PSYoungGen: 932534K->93...

Does variable = null set it for garbage collection

Help me settle a dispute with a coworker: Does setting a variable or collection to null in Java aid in garbage collection and reducing memory usage? If I have a long running program and each function may be iteratively called (potentially thousands of times): Does setting all the variables in it to null before returning a value to the pa...

Cost of logic in a query

I have a query that looks something like this: select xmlelement("rootNode", (case when XH.ID is not null then xmlelement("xhID", XH.ID) else xmlelement("xhID", xmlattributes('true' AS "xsi:nil"), XH.ID) end), (case when XH.SER_NUM is not null then xmlelement("serialNumber", XH.SER_NUM) ...

Can you get a Func<T> (or similar) from a MethodInfo object?

UPDATE: The suggestion to use an expression tree to construct a lambda using the given MethodInfo, in conjunction with the Expression<TDelegate>.Compile method, proved to be a gold mine in my scenario. In the specific case where I was toying with this idea, I saw average execution time for a particular method go from ~0.25 ms to ~0.001 m...

EntityFramework performance problem

I'm using EntityFrameowrk 4 and WinForms. I have a DataGridView which shows 5 to 12 thousands of records. The records are from different levels of hierarchy. There are records of classes A, B, C, D, where A contains a collection of B, B contains a collection of C, etc. The most numerous class is D. In the DataGridView this hierarchy is f...

Cache of Objects or OutPut in View ? Wich is better ?

Hi everybody, I have an ecommerce working in ASP.Net MVC. i'm using Caching to improve more performace in my pages and it's working fine. I'd link to know what is more performative, for example, I can set OutPutCache in my views and and use this cache for all page OR I could get my List of Products in controller, put it on cache (lik...

Displaying performance metrics in a modern web app?

We're updating our ancient internal PHP application at work. Right now, we gather extensive performance measurements on every pageview, and log them to the database. Additionally, users requested that some of the metrics be displayed at the bottom of the page. This worked out pretty well for us, because the last thing that the applica...

Does having a longer string in a SQL Like expression allow hinder or help query executing speed?

I have a db query that'll cause a full table scan using a like clause and came upon a question I was curious about... Which of the following should run faster in Mysql or would they both run at the same speed? Benchmarking might answer it in my case, but I'd like to know the why of the answer. The column being filtered contains a couple...

javascript object access performance

In Javascript, when your getting a property of an object, is there a performance penalty to getting the whole object vs only getting a property of that object? Also Keep in mind I'm not talking about DOM access these are pure simple Javascript objects. For example: Is there some kind of performance difference between the following cod...

XMLWriter vs SimpleXML. Which one is faster?

I basicly need to load the whole XML file, add a new line with content and then saving it. But I wondered which one is faster.. XMLWriter or SimpleXML? Oh, and, it's mainly large XML files, more then 10MB. Thanks! ...

Increase performance on iphone at pdf rendering

Hi! I have a UITableView, and in every cell there's displayed a UIImage created from a pdf. But now the performance is very bad. Here's my code I use to generate the UIImage from the PDF. Creating CGPDFDocumentRef and UIImageView (in cellForRowAtIndexPath method): ... CFURLRef pdfURL = CFBundleCopyResourceURL(CFBundleGetMainBundle(...

Optimizing MySql query to avoid using "Using filesort"

I need your help to optimize the query to avoid using "Using filesort".The job of the query is to select all the articles that belongs to specific tag. The query is: select title from tag, article where tag = 'Riyad' AND tag.article_id = article.id order by tag.article_id The tables structure are the followi...