Performance-Related InformationChapter 18 Configuring IM Presence Information 495The file lists the default object classes with the allowed attributes that must beadded to a user’s entry in order for presence information to be available for thatuser:objectclass: nsAIMpresenceattributeTypes: nsAIMid syntax DirectoryStringattributeTypes: nsAIMStatusGraphic syntax BinaryNO-USER-MODIFICATION USAGE directoryOperationattributeTypes: nsAIMStatusText syntax DirectoryStringNO-USER-MODIFICATION USAGE directoryOperationobjectclass: nsICQpresenceattributeTypes: nsICQid syntax DirectoryStringattributeTypes: nsICQStatusGraphic syntax BinaryNO-USER-MODIFICATION USAGE directoryOperationattributeTypes: nsICQStatusText syntax DirectoryStringNO-USER-MODIFICATION USAGE directoryOperationobjectclass: nsYIMpresenceattributeTypes: nsYIMid syntax DirectoryStringattributeTypes: nsYIMStatusGraphic syntax BinaryNO-USER-MODIFICATION USAGE directoryOperationattributeTypes: nsYIMStatusText syntax DirectoryStringNO-USER-MODIFICATION USAGE directoryOperationYou can create your own schema and modify the plug-in configuration parametersaccordingly. For more information about Directory Server schema, check theNetscape Directory Server Schema Reference.Performance-Related InformationNote the following:• The Presence plug-in provides the presence information through an HTTPinterface. That is, for every request for IM Status, the plug-in makes an HTTPrequest to the IM server. Hence, enabling this feature for a large number ofusers may degrade the performance of Directory Server when manysimultaneous requests are issued for the presence status of many users.• Currently there’s no caching support for this feature. Potentially, all thethreads in the Directory Server may be waiting for an HTTP response.Additional requests, including requests that do not include presenceinformation, will not complete until one or more of the presence informationrequests has completed. To avoid such a situation, you can set resource limitsbased on bindDN as explained in the next section.
