performance

Good .NET library for fast streaming / batching trigonometry (Atan)?

I need to call Atan on millions of values per second. Is there a good library to perform this operation in batch very fast. For example, a library that streams the low level logic using something like SSE? I have profiled the application, and I know that this call to Atan is a bottleneck. I know that there is support for this in Open...

SQL Server performance issue.

Hi Friends, I have been trying to analyze performance issue with SQL Server 2005. We have 30 jobs, one for each databases (30 databases, one per each client). The jobs run at early morning at an interval of 5 minutes. When I run the job individually for testing, for most of the databases it finishes in 7 to 9 minutes. But when these j...

How do I make "simple" throughput servlet-filter?

I'm looking to create a filter that can give me two things: number of request pr minute, and average responsetime pr minute. I already got the individual readings, I'm just not sure how to add them up. My filter captures every request, and it records the time each request takes: public void doFilter(ServletRequest request, ...() { ...

Getting "on the wire" Size of Messages in WCF

While I'm making SOAP or REST invocations to WCF, I'd like to have the channel stack on either end (client and server) record the on-the-wire size of the data received. So I'm guessing I need to add a custom behavior to the channel stack on either side. That is, on the server side I'd record the IP-header advertised size that was recei...

Browser timing out attempting to load images

I've got a page on a webapp that has about 13 images that are generated by my application, which is written in the Kohana PHP framework. The images are actually graphs. They are cached so they are only generated once, but the first time the user visits the page, and the images all have to be generated, about half of the images don't load...

weird performance in C++ (VC 2010)

Hello, I have this loop written in C++, that compiled with MSVC2010 takes a long time to run. (300ms) for (int i=0; i<h; i++) { for (int j=0; j<w; j++) { if (buf[i*w+j] > 0) { const int sy = max(0, i - hr); const int ey = min(h, i + hr + 1); const int sx = max(0, j - hr); c...

Working with a large data object between ruby processes

I have a Ruby hash that reaches approximately 10 megabytes if written to a file using Marshal.dump. After gzip compression it is approximately 500 kilobytes. Iterating through and altering this hash is very fast in ruby (fractions of a millisecond). Even copying it is extremely fast. The problem is that I need to share the data in this...

mysql query building output taking a long time

I have a simple query that does select * from t limit 1; on a remote mysql server. I use squirrel(mysql client) to run it, it shows: Query 1 of 1 elapsed time (seconds) - Total: 22.047, SQL query: 1.047, Building output: 21 why does building output take such a long time? what does this process do? when running from mysq...

Is there a Better Way to Retreive Raw XML from a URL than WebClient or HttpWebRequest? [.NET]

I am working on a Geocoding app where I put the address in the URL and retreive the XML. I need the complete XML response for this project. Is there any other class for downloading the XML from a website that may be faster than using WebClient or HttpWebRequest? Can the XMLReader be used to get the full XML without string manipulation...

MySQL resource usage

I'm using MySQL with PHP. I want to measure how much memory and other resources MySQL is using when I run a particular query ...

Optimize a views drawing code

Hi, in a simple drawing application I have a model which has a NSMutableArray curvedPaths holding all the lines the user has drawn. A line itself is also a NSMutableArray, containing the point objects. As I draw curved NSBezier paths, my point array has the following structure: linePoint, controlPoint, controlPoint, linePoint, controlPo...

Performance of inter-database query (between linked servers)

I have an import between 2 linked servers. I basically got to get the data from a multiple join into a table on my side. The current query is something like this: select a.* from db1.dbo.tbl1 a inner join db1.dbo.tbl2 on ... inner join db1.dbo.tbl3 on ... inner join db1.dbo.tbl4 on ... inner join db2.dbo.mysid...

Are there performance problems in querying non varbinary(max) fields in a table containing varbinary(max) data?

I created a table to insert all the documents of my application. It is a simple table (let's call it DOC_DATA) that has 3 fields: DOC_ID, FileSize, Data. Data is varbinary(max). I then have many tables (CUSTOMERS_DOCUMENTS, EMPLOYEES_DOCUMENTS, ...) that contain other data (like "document description", "Created by", "Customer ID" ...). ...

Inserting asyncronously into Oracle, any benefits?

I am using ODP.NET for loading data into Oracle. I am bulking inserts into groups of a 1000 rows each call. Is there any performance benefits in calling my load method asynchronously? So say I want to insert 10000 rows, instead of making 10 calls synchronously I make 10 calls asynchronously. My database is using ASSM right now but oth...

Performance impact when UseLayoutRounding = true

I'm wondering if there is any impact on performance when I will set UseLayoutRounding = true for almost all controls in my LOB application. Especially texts looks bad if there is no layout rounding. I'm working on Silverlight 3.0 but soon I'll migrate to 4.0. ...

Even lighter than SQLite

I've been looking for a C++ SQL library implementation that is simple to hook in like SQLite, but faster and smaller. My projects are in games development and there's definitely a cutoff point between needing to pass the ACID test and wanting some extreme performance. I'm willing to move away from SQL string style queries, allowing it to...

MySql: make this query faster... is there a way ?

There are 4 tables: Books : id, name, author, ecc... Category : id, name Library : id, name, street, city, ecc.. bookcorr : book_id, category_id, library_id Ids are all keys. The query must show the categories with the numbers of books in a defined Library. for ex: Library X: Romantic (50) Yellow (40) Scien...

MySql: make this query faster… is there a way ? PART TWO

This is part two of the question: http://stackoverflow.com/questions/2913639/mysql-make-this-query-faster-theres-a-way this query still run slowly: SELECT b.id, b.name, c.name FROM bookcorr as a JOIN books as b on b.id = a.books_id = JOIN Library as c on c.id = a.library_id WHERE a.category_id = '2521' AND a.library_id ...

WPF Application Typing in Custom TextBox CPU Jumping from 3 to 80 percent

I have created a RichTextBox called SharpTextBox which indicates and limits the number of characters that can be typed in it. The implementation is shown in the following link: http://www.highoncoding.com/Articles/673_Creating_SharpRichTextBox_for_Live_Character_Count_in_WPF.aspx Anyway when I start typing in the TextBox it goes from...

Does it make a difference in performance if I use self.fooBar instead of fooBar?

Note: I know exactly what a property is. This question is about performance. Using self.fooBar for READ access seems a waste of time for me. Unnecessary Objective-C messaging is going on. The getters typically simply pass along the ivar, so as long as it's pretty sure there will be no reasonable getter method written, I think it's perfe...