Running the Page Server as an NT Service

On Windows NT systems, the Page Server can be set up to run as an NT service. It is installed under a system account by default. NT services run in the background and do not require a user or administrator to be logged on to the web server machine. Most web server systems should run the Page Server as an NT service for best performance.

The Page Server appears as Crystal Web Page Server in the Windows NT Services control panel.

Job Manager Overview

Page caching and job sharing are implemented via the Job Manager (CRJM). This section provides a general description of the Job Managers function as it concerns Job Sharing and Page Caching:

When a client requests a report, that has not been requested before, the following occurs:

●A new report Job is created. A cache is created, which will hold report pages as they are requested. A reference to the report job is created. The reference has a unique id (Request Id) by which the client can access the job in the future.

●There is usually a refresh interval associated with a report job.This is the time interval (specified as the Database Refresh Time in the Configuration Manager) after which a new request for the same report will result in accessing the database for updated information. In other words if a new client requests the report after the refresh interval for the existing report job then new report job is created as a result.

●If a client referencing an existing report job selects refresh then a new report job is created and the client gets a reference to the new job.

Job Sharing

If the report contains saved data and there are no SF# and GF# commands or if a report does not have saved data and there ar no SF#,GF#,PASSWORD#,USER#,PROMPT# or promptOnRefresh# commands then the resulting report job can be shared. What this means is that requests for the same report (which occur within the same refresh interval) will result in references to the same report job.

There are conditions under which a shared report job will no longer be shared:

●If a client sharing an existing report job selects refresh then a new report job will be created and the client will receive a reference to the new report job.

●If a client sharing an existing report job submits a page request that includes one of the commands listed previously then a new report job will be created and the client will receive a reference to the new report job.

Page Caching

Associated with each report job is a cache to store requested pages. The pages are generated as requested, passed to the client and stored in the cache. If another client, who is sharing the same report job, requests a page which is already cached then that client will received the cached page. This can greatly reduce access time (subject to the traffic conditions of your network at any given time).

Job Examples

Reports with Saved Data

A report that is saved with data and does NOT have the sf or gf parameters applied to it, will have its pages shared by all users. If the report has the gf or sf parameters applied, the caching will be by user (same as Crystal Reports 6.0).

Reports without Saved Data

A report without saved data that does NOT have the sf, gf, user#, password#,promptOnRefresh, or prompt# parameters applied to it, will have its pages shared by all users. Due to the reports not being saved with data, the user must specify the database refresh time interval in the Web Reports Server Configuration utility. This interval indicates how often the database will be accessed. For example:

1.The database refresh time is set to 5 minutes.

2.User A selects report A1 (without saved data). Since User A is the first person to select this report, the database is accessed.

3.Two minutes after User A requested Report A1, User B selects Report A1. User A and User B will share the report's pages because the report was requested before the database refresh time expired. Thus, the database is not accessed.

4.Six minutes after User A requested Report A1, User C selects Report A1. Since the database refresh time interval has expired (the setting is 5 minutes and 6 minutes have passed since the database was accessed for this report), the database will be accessed and User C will not share his pages with User A and User B.

5.One minute after User C requested Report A1, User A selects his viewer's refresh button. User A and User C will share cached pages because User A requested accessing the database inside the database refresh time interval. The database was accessed one minute before by User C, and the database refresh time is 5 minutes.

6.Four minutes after User C requested Report A1, User B selects his viewer's refresh button. User B, User A and User C will share cached pages because User B requested accessing the database inside the database refresh time interval. The database was accessed four minutes before by User C, and the database refresh time is 5 minutes.

7.If the report has the sf, gf, user#, password#, promptOnRefresh#, or prompt# parameters applied, the caching will be by user (same as Crystal Reports 6.0).

What you will find in this chapter...

Note: This chapter contains information specific to the

Professional Edition of Seagate Crystal Reports.

Seagate Crystal Report Engine Automation Server, Page 44

Visual InterDev Design-time ActiveX Control, Page 44

...including an overview, using an existing report, and building a report at runtime.

Editing Active Server Pages, Page 47

...including customizing the Smart Viewer, modifying the report, and session timeouts.

Sample Web Site, Page 48