Introduction to Diagnostic Solutions

Using Diagnostic Features 8-3 Using the Server response header information, you can determine whether a request was served from the cache or the origin server. In the following example, the Server field specifies that the object was a cache hit: Server: Oracle Fusion Middleware 11g 11.1.1.0.0 Oracle-HTTP-Server Oracle-Web-Cache-11g11.1.1.0.0 TH;max-age=60+30;age=55;ecid=23248098121,0 TH;max-age=60+30;age=55;ecid=23248098121,0 is the diagnostic information. ■ T means this page is composed by ESI ■ H means this request resulted in cache hit ■ max-age=60+30 means that the object is to expire in 60 seconds from population and to be removed from the cache 30 seconds from the expiration. This provides a total of 90 seconds from population. ■ age=55 in age means that 55 seconds have passed since population of the cache, meaning there are 5 seconds to expiration and 35 seconds to removal ■ ecid=23248098121,0 specifies the request ID and sequence number from the Oracle-ECID request header. To display the Server response header in the access logs, you select the scServer field. You must configure the scServer field as a user-defined access log format. For more information, see: ■ Section 9.4 for further information about creating a user-defined access log format that includes the scServer field ■ Section 8.8 for configuring the display of diagnostics information Table 8–1 Control Directives for Server Control Directive Description ESI_processing_type ESI_processing_type is: ■ T specifies that the object is an ESI template ■ F specifies that the object is an ESI fragment ■ empty specifies that the response does not require ESI processing cache_request_type cache_request_type is: ■ H specifies a cache hit ■ S specifies a cache hit of a stale object ■ U specifies a cache update of a stale object ■ G specifies a cache update of an object that was marked for removal but still physically resides in the cache ■ M specifies a cache miss ■ N specifies a non-cacheable cache miss max-age=expiration_ time [+removal_time] Specifies the time, in seconds, to expire the object, and optionally, the time, in seconds, to remove the object from the cache after the expiration time. max_age does not appear if the cache_request_type is N. age=object_age Shows how long, in seconds, the object has been in the cache. age does not appear if the object is non-cacheable ecid=request_ID, sequence_number Specifies the request ID and sequence number specified in Oracle-ECID request header: