I am assigned to a performance-tuning-debugging-troubleshooting task. Scenario: a multi-application environment running on several networked machines using databases. OS is Unix, DB is Oracle. Business logic is implemented across applications using synchronous/asynchronous communication. Applications are multi-user with several hundred ...
Hi, I have a question regarding a semi-constant update in a database. In short it is regarding a checkout function on a web page, which each time the checkout function is evoked it do five steps. I want to try to optimize this function and have my eye on a step where I update a table each time the checkout is performed. I take the info...
I've gotten to that point in one of my projects, and haven't found much information out there. So if you've got some pointers for improving performance in the new Entity Framework 4, please let us know! ...
Hi everybody! In a ASP.MVC (1.0) project i managed to get weather info from a RSS feed and to show it up. The problem i have is performance: i have put a RenderAction() Method in the Site.Master file (which works perfectly) but i 'm worried about how it will behave if a user clicks on menu point 1, after some seconds on menu point 2, a...
Hi, I am running some queries in my database and want to increase the performance and have created some indexes but I still think that the response time is to great so I want to see if I can create a better or another index to increase the speed. My schema for the table I think has the biggest bottleneck look like this: R_D( **id** i...
A little background on the application that I am gonna talk about in the next few lines: XYZ is a data masking workbench eclipse RCP application: You give it a source table column, and a target table column, it would apply a trasformation (encryption/shuffling/etc) and copy the row data from source table to target table. Now, when I ma...
I just tried running a program that I've been developing with Qt outside of Qt. I double clicked on the program in /release, resolve all the missing DLLs, and find that my app has awful slow performance compared to when it is launched from within Qt Creator. What might be the reason for this?! ...
Lets be honest, most software that developers produce has quite modest performance requirements. E.g. Systems perhaps serving 100's of requests per second, if that. But lets assume for a moment (or even dream) that you where perhaps involved in the "next big thing" (whatever that means) and you wanted to put some sort of performance sta...
Hi, I have a jvm server in my machine, now I want to have 2 apservers of mine sitting in same machine, however I want the standby one to have a really low amount of memory allocated with xmx because its passive, one the main server (active) goes down I want to allocate more memory to my passive server which is already up without restart...
Hi, I have a simple users table, i guess the maximum users i am going to have is 300,000. Currently i am using: CREATE TABLE users ( id INT UNSIGEND AUTOINCEREMENT PRIMARY KEY, .... Of course i have many other tables that the users(id) is a FOREIGN KEY in them. I read that since the id is not going to use the f...
Do you see a better approach to obtain and concatenate item.Number in a single string? Current: var numbers = new StringBuilder( ); // group is the result of a previous group by var basenumbers = group.Select( item => item.Number ); basenumbers.Aggregate ( numbers, ( res, element ) => res.AppendFormat( "{0:00}", element ) ); ...
Last night I did a load test on a site. I found that one of my shared caches is a bottleneck. I'm using a ReaderWriterLockSlim to control the updates of the data. Unfortunately at one point there are ~200 requests trying to update the data at approximately the same time. This also coincided with CPU usage spikes. The data being updated ...
I have a very large nested for loop in which some multiplications and additions are performed on floating point numbers. for (int i = 0; i < length1; i++) { double aa = 0; for(int h = 0; h < 10; h++) { aa += omega[i][outsideGeneratedAddress[h]]; } double alphaOld = alpha; alpha = Math.Sqrt(alpha * alpha ...
Hi, I am trying to find a solution for a problem that is driving me mad... I have a query which runs very fast in a QA Server but it is very slow in production. I realized that they have different execution plans... so I have try recompiling, cleanning the cache for the execution plans, update statistics, check the type of collation......
Hi, I'm asked to shorten the start-up period of a long starting app, however I have also to obligate to my managers to the amount of time i will reduce the startup - something like 10-20 seconds. As I'm new in my company I said I can obligate with timeframe of months (its a big server and I'm new and I plan to do lazy load + performanc...
Can anyone recommend a web site that includes up to date performance tips for Java? Most of the sites I have found seem to be old and I guess the newer versions (1.5 - 1.7) may have obsoleted some recommendations. Edit: I'm mostly concerned with reducing memory usage/garbage collection and making sure that simple methods can be inlined...
There seems to be a general conclusion floating around the internet that external js files are better. The main reasons are caching, maintenance, and debugability. However there does not seem to be much discussion on the overhead of the 304 http requests. I went to yahoo.com, and noticed that 304's for each javascript file has an overh...
I am trying to improve the performance of a SSIS Package. One thing I got startted with is to filter the reference table of the Lookups. Until now, I was using a table as a reference table for that lookup. First improvment was to change the table to a SQL clause that is selecting just the columns I need from that table. Next, I want...
i have a function who's job is to convert an ADO Recordset into html: class function RecordsetToHtml(const rs: _Recordset): WideString; And the guts of the function involves a lot of wide string concatenation: while not rs.EOF do begin Result := Result+CRLF+ '<TR>'; for i := 0 to rs.Fields.Count-1 do ...
Or decide between a parallel and a sequential operation in general. It is hard to know without testing whether parallel or sequential implementation is best due to overhead. Obviously it will take some time to train "the decider" which method to use. I would say that this method cannot be perfect, so it is probabilistic in nature. The x,...