I have a SQL query - fairly complex, but not too bad. When I run the SQL query in Management Studio, the query runs in about 10 seconds or less. When I put the SQL query directly into a reporting services report, the query runs in about 10 seconds or less. When I put the exact same SQL query into a stored procedure, and cal...
I've got an interresting problem: Given an IEnumerable<string>, is it possible to yield a sequence of IEnumerable<string> that groups identical adjacent strings in one pass? Let me explain. 1. Basic illustrative sample : Considering the following IEnumerable<string> (pseudo representation): {"a","b","b","b","c","c","d"} How to get...
I run massively parallel scientific computing jobs on a shared Linux computer with 24 cores. Most of the time my jobs are capable of scaling to 24 cores when nothing else is running on this computer. However, it seems like when even one single-threaded job that isn't mine is running, my 24-thread jobs (which I set for high nice values)...
I have been using VS2010 with Resharper 5 for several weeks and am having a performance issue. Sometimes when typing, the cursor will lag and the keystrokes won't show instantaneously. Also, scrolling will lag at times. There is a forum thread started and JetBrains has been responding. Several people (including myself) have added their...
Hello, I am trying to determine document similarity between a single document and each of a large number of documents (n ~= 1 million) as quickly as possible. More specifically, the documents I'm comparing are e-mails; they are grouped (i.e., there are folders or tags) and I'd like to determine which group is most appropriate for a new...
I'm creating a new Client / Server application in C# and expect to have a fairly high rate of connections. That made me think of database connection pools which help mitigate the expense of creating and disposing connections between the client and database. I would like to create a similar capability for my application and haven't been...
Is there a tool that would show me for a specific file on disk, how fragmented it is? (How many seeks does physical disk need to make if I were to read that file in a linear fashion) ...
Hi, I have ported a piece of C++ code, that works out of core, from Linux(Ubuntu) to Windows(Vista) and I realized that it works about 50times slower on VS2008! I removed all the out of core parts and now I just have a piece of code that has nothing to do with the hard disk. I set compiler parameters to O2 in Project Properties but sti...
In Python, which data structure is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list? ...
I'm trying to overcome a very serious performance issue in which Sybase refuses to use the primary key index on a large table because one of the required fields is specified indirectly through another table - or, in other words; SELECT ... FROM BIGTABLE WHERE KFIELD = 123 runs in ms but SELECT ... FROM BIGTABLE, LTLTBL WHERE KFIELD =...
I need to process a list of files. The processing action should not be repeated for the same file. The code I am using for this is - using namespace std; vector<File*> gInputFileList; //Can contain duplicates, File has member sFilename map<string, File*> gProcessedFileList; //Using map to avoid linear search costs void processFile(Fi...
Hi to all, As I mention in an earlier question, I am having trouble with the performance of a web site... Some SQL queries are killing the server. But, as the title of this post mention, I looked at the OutputCache page directive to improve performance of the site. Although, I came across some questions regarding this directive: 1- If ...
Considering the code below: Dataview someView = new DataView(sometable) someView.RowFilter = someFilter; if(someView.count > 0) { …. } Quite a number of articles which say Datatable.Select() is better than using DataViews, but these are prior to VS2008. Solved: The Mystery of DataView's Poor Performance with Large Recordsets Array...
My slow query log is full of entries like the following # Query_time: 1.016361 Lock_time: 0.000000 Rows_sent: 0 Rows_examined: 0 SET timestamp=1273826821; COMMIT; I guess the set timestamp command is issued by replication but I don't understand how set timestamp can take over a second. Any ideas? ...
I have a picturebox where I change the BackgroundImage frequently. I have a the BackgroundImageLayout set to Zoom. The problem is that when an image does not have the same scale as the picturebox, the picture is drawn in the middle. That is, the top and the bottom padding of the picturebox is always the same. I would like for the Bac...
Hi all, I am seeking to (legitimately) plant bugging in my web pages to collect and report information about website performance. Preference for internally hosted. While I expect that there are commercial offerings out there (e.g. Google Analytics) I'm keen to find something we can run entirely in-house (its not a public website and m...
Dear fellows, I'm looking for a reference to cite, which states that JSF 1.2 performs better than JSF 1.1. Or JSF 2.0 over JSF 1.2 respectively. I'm quite sure that I've read something like this before but can't find it anymore. Maybe you can help. Or is this mischief and there are no official statements regarding the performance? ...
I have written two simple programs (tried it in C++ and C#). This is pseudo code: -------- Client --------------- for(int i = 0; i < 200.000; i++) { socket_send("ping") socket_receive(buff) } --------- Server ------------- while(1) { socket_receive(buff) socket_send("pong") } I tried ...
I have a table Car in my db, one of the columns is purchaseDate. I want to be able to tag every car with a number of Policies (limited to 10 policies). Each policy has a time to life (ttl, a duration of time, like '5 years', '10 months' etc), that is, for how long since the car's purchaseDate the policy can be applied. I need to perfor...
I am looking to make a hefty shift towards templates in one of my OpenGL projects, mainly for fun and the learning experience. I plan on watching the size of the executable carefully as I do this, to see just how much of the notorious bloat happens. Currently, the size of my Release build is around 580 KB when I favor speed and 440 KB ...