IBM Cognos 8 servers use a variety of directory access depending on the type and amount of activity. For running reports, IBM Cognos 8 servers frequently use temporary space. We recommend that the IBM Cognos 8 temporary space be hosted on a physical disk that is separate from other IBM Cognos 8 directory locations. This maximizes parallel disk access and avoids the unnecessary sequential access that is common when only a single disk device is used.
Depending on the size of reports and the amount of available memory, IBM Cognos 8 may access a physical disk when processing reports. To improve performance, you can ensure that report processing uses available memory rather than disk space.
Using memory instead of disk space is particularly beneficial in cases where temporary files are created on IBM Cognos 8 servers, causing information transfer from memory to disk. You can monitor the occurrence of temporary files using the c8_location\temp directory. Monitor this folder during report processing periods to determine whether temporary files are created as cclvpage*.tmp.
To ensure that IBM Cognos 8 uses memory instead of disk space, in the rsvpproperties.xml file, edit the VirtualMemoryDiagnostics property to use unlimited memory (value = 2) rather than limited memory (value = 0):
<property>VirtualMemoryDiagnostics</property>
<value type="long">2</value>
Note: Remove the comment to enable the VirtualMemoryDiagnostics property.
For information about using the rsvpproperties.xml file, see Advanced Report Processing Configuration Settings.