SSRS throws "The operation has timed out."

Reporting Services in integrated mode sometimes throws "The operation has timed out."

when render report through application.
The solutions for this problem are listed below:
1. ReportingService2010 reportingService2010=new ReportingService2010();
reportingService2010.Timeout=120000;

or
2. In SharePoint integrated mode, the default timeout is 120 seconds, which is
the default timeout of IIS. We can change it by updating "web.config".
open "c:\inetpub\wwwroot\wss\VirtualDirectories\80\web.config",
locate <httpruntime maxrequestlength="51200"/>,
and change this sentence to
<httpruntime maxrequestlength="51200" executionTimeout="9000"/>