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ASP.NET PDF Viewer using C#, VB/NETIf this comes as a surprise to you, it s going to come as an absolute shock what happens with memory consumption during this process (see Figure 3-19). Carefully consider the resources you re consuming when you re binding a DataGrid to a DataSet with the following code: private void Page_Load (object sender, System.EventArgs e) { SqlConnection cn = new SqlConnection("server=.;database=pubs;uid=sa;pwd="); SqlCommand cm = new SqlCommand("select * from authors", cn); SqlDataAdapter da = new SqlDataAdapter(cm); DataSet ds = new DataSet(); da.Fill(ds); DataGrid1.DataSource = ds.Tables[0]; DataGrid1.DataBind(); } //Page Rendering excel barcode font not working, excel vba barcode generator, download barcode macro for excel, free barcode add in for word and excel, vba code for barcode in excel, excel barcode font 2016, barcode add in excel 2003, barcode generator excel free download, barcode erstellen excel freeware, excel 2007 barcode add in,Performance/scalability: Since this connection is dedicated to Tony, the resources associated with the connection can t be used by anyone else until Tony logs off or his connection times out. Moreover, the connection has to be established and torn down each time Tony logs into or out of the application. If you increase the connection timeout period, there will be more idle time for the connection, resulting in more wasted resources. On the other hand, if you reduce the connection timeout, Tony would see performance problems associated with connection creation and destruction overhead that occurs after each timeout. Thus, the idea of dedicating one connection for one user for the lifetime of an application session can be a significant scalability inhibitor when we deal with a large number of users. system calls requires that the calling convention adopted by the operating system is implemented, and it is often used to interact with different runtimes Another popular approach is to support the calling convention adopted by C compilers because it is widely used and has become a fairly universal language for interoperability Note that although many operating systems are implemented in C, the libraries providing system calls may adopt different calling conventions This is the case of Microsoft Windows where the operating system adopts the so-called stdcall calling convention rather than the C calling convention A significant dimension in the arena of possible calling conventions is the responsibility for removing the activation record from the thread stack At first glance, it may seem obvious that it is the called function that before returning resets the stack pointer to the previous state. Figure 3-19. Consumption of resources while data binding The first hit you take on the web server s memory is when you call Fill on the DataAdpater. This marshals your entire result set from the database into the process space of the web server. The DataSet carries not only the current values as read from the database, but also the original values as the data was read out of the database, as well as metadata about the structure of the DataTable objects contained in its TablesCollection. The DataSet is a very powerful object, but it s also a very fat object. You take a hit whenever you load one into memory. If you re doing this on your home page, you re taking this hit not once, but once for each user that comes to your site. But wait, it gets worse. The next thing you do is set the DataSource of the DataGrid and call DataBind. As we just went over, this creates an in-memory collection of DataGridItems. This collection is probably just as large as your DataSet. If you re only outputting a couple of columns, maybe it won t be as large. If you re using a complex column template with a lot of markup, the size of this
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