performance-tuning

What is the best way scale out work to multiple machines?

We're developing a .NET app that must make up to tens of thousands of small webservice calls to a 3rd party webservice. We would prefer a more 'chunky' call, but the 3rd party does not support it. We've designed the client to use a configurable number of worker threads, and through testing have code that is fairly well optimized for on...

JVM performance tuning for large applications

The default JVM parameters are not optimal for running large applications. Any insights from people who have tuned it on a real application would be helpful. We are running the application on a 32-bit windows machine, where the client JVM is used by default. We have added -server and changed the NewRatio to 1:3 (A larger young generation...

Best way to speed up MS SQL server

I was wondering if anyone has some general sys admin questions on how best to setup MS SQL server for speed. I have placed the log files on a different drive with its own controller and moved the indexes to their drive but on the same controller as the main data files. What other way can a system admin setup MS SQL server to speed up di...

Improving performance of cluster index GUID primary key

Hi, I've a table with large number of rows (10K+) and it primary key is GUID. The primary key is clustered. The query performance is quite low on this table. Please provide suggestions to make it efficient. ...

updating win32_printer management object takes so long

I use following piece of code to change printers "port" property. Problem is it executes longer than a minute. Is there a way to speed it up? Can i instantiate management object not with all properties of wmi object? And more importantly, how can i update only 1 property? Maybe i should instantiate managementobject withouth searcher? M...

Improving cURL performance (PHP Library)

Here is a brief overview of what I am doing, it is quite simple really: Go out and fetch records from a database table. Walk through all those records and for each column that contains a URL go out (using cURL) and make sure the URL is still valid. For each record a column is updated with a current time stamp indicating when it wa...

How can I learn SQL Server index tuning?

What is the best practical way of learning index tuning while writing tsql queries? I have VS2008 SQL Express. Could someone please provide me examples, etc? I have already found online articles and they are great in theory, but I still fail to see index tuning in real life action. Are there small easy to create examples out there? ...

Speed up your IIS

Hi! Is there any way to improve the performance of your IIS by changing some configuration parameters? Or do you have any tips in general on how to improve the performance of a ASP.NET app? Thanks! ...

SQL Server 2005 Memory Pressure and tempdb writes problem

We are having some issues with our production SQL Server. Server: Dual Quad Core Xeon 8 GB RAM Single RAID 10 Array Windows 2003 Server 64-bit SQL Server 2005 Standard 64-Bit There is about 250MB of free RAM on the machine right now. SQL Server has around 6GB of RAM, and our monitoring software says that only half of the SQL Server al...

Has anyone found Garbage Collection tuning to be useful?

I've read plenty of articles about tuning GC in Java and have often wondered how many people really use some of the more advanced features. I've always avoided tuning where possible and concentrated on writing the simplest possible code I can (Brian Goetz's advice) - this seems to have worked well for me so far. Are these tuning strate...

JSF Tuning

Running into an issue where JSF is filling up our sessions. We had a system crash the other day. Sent the Heap to IBM for review and found that we had some sessions as large as 50M. They found JSF components in the session and some very large. So, is there any tuning that can be done? Configuration items to look at? Or other directi...

improving sql server query response time.

I have a table which contains around 4 lakh records and which gets called on the homepage of the intranet website. At peak times we can have 300-400 concurrent users. The SQL Profiler tool gives the following output. CPU: 406, Reads: 32446, Duration: 397. Q1. I have indexed the fields involved in the 'where' clause. Is there a way to ...

Performance counters on the iPhone

I'm trying to find the best method of incode performance monitoring on the iPhone. On a windows platform I would use the following functions : QueryPerformanceCounter((LARGE_INTEGER *)&ctr); QueryPerformanceFrequency((LARGE_INTEGER *)&freq); Does anything like this exist on the iPhone? Whats the highest resolution I can time something...

huge svn checkout made apache (dav_svn) consume all memory on server - any tips?

Are there any settings in apache2/dav_svn/ssl/subversion on the server that would make the whole perform better (or at least not consume all memory) on big checkouts? I'm especially interested in suggestions on how to keep memory consumption down. Reason for this question: Last week we had an issue with our svn server - it stopped res...

Missing Join Predicate Warning

I'm running a SQL Server 2005 trace using profiler. I'm seeing some missing join predicate warnings, but I can't determine where its occurring with the data they are giving me. All I have is the transactionID. Any way to find out what object is causing this? ...

Optimizing MySQL for ALTER TABLE of InnoDB

Sometime soon we will need to make schema changes to our production database. We need to minimize downtime for this effort, however, the ALTER TABLE statements are going to run for quite a while. Our largest tables have 150 million records, largest table file is 50G. All tables are InnoDB, and it was set up as one big data file (instead ...

Tricks to speed up Jboss Seam debug cycle

We deploy and debug a Jboss Seam 2.0 EAR app from within eclipse, booting it on Jboss AS 4.2.2. Right now we need to reboot it every time we change the message bundle, pages.xml, components.xml, or the model, which takes up to 45 seconds. Is it possible to include aforementioned files in hot deployment, and what are the options for boos...

What's wrong in terms of performance with this code? List.Contains, random usage, threading?

I have a local class with a method used to build a list of strings and I'm finding that when I hit this method (in a for loop of 1000 times) often it's not returning the amount I request. I have a global variable: string[] cachedKeys A parameter passed to the method: int requestedNumberToGet The method looks similar to this: List...

What causes large Pending Reads / Writes in MySQL with InnoDB tables? How can I prevent them?

I have a MySQL database that has on the order of 400 million innodb_data_pending_reads and innodb_pending_writes. My other databases are consistently at or near zero, so I noticed this large outlier. What can cause this situation? What adverse affects can it cause? How can I troubleshoot the situation to bring this down? ...

Oracle materialized view tuning

I am trying to perform tuning of materialized views in my application. I set out to execute: dbms_advisor.tune_mview() procedure, and wrote the following code into an SQL_Worksheet of Oracle SQL Developer: variable mvtask varchar2(100); variable mvddl varchar2(4000); execute :mvtask := 'MV_FOO_BAR'; execute select query into :mvdd...