Session-Based Processing Method and System

Abstract

A log file processing system sorts records from large log files and groups them by session without making a complete copy of the log files by capturing a subset of the log files in a sliding memory window and identifying all records in the window that form a complete user session. Records belonging to a complete session are output for analyzing, and the remaining records are output as raw log data for additional processing. Using a ring buffer to implement the sliding memory window, data structures are used to group records by session, to identify completed sessions, and to index into the ring buffer to retrieve records for completed sessions that are to be directly analyzed. Any records remaining in the ring buffer at the end of slide window processing may be output as raw log file data and are processed as incomplete or malformed session records. An embodiment of the log file processing system provides a significant improvement on the speed of data extraction from log files into analyzable session data.

What is claimed is: 
     
         1 . A method for grouping log file entries by session, comprising:
 storing a log file of entries in a memory, each of said entries identifying a client request to a server;   retrieving a subset of log file entries from the memory;   identifying each entry in the memory to identify entries in the subset of log file entries that belong to a complete client session;   grouping entries in the subset that belong to a complete client session.   
     
     
         2 . The method of  claim 1 , wherein a complete client session is identified by identifying all entries in the subset that are associated with a particular client session and that include both a beginning entry and an end entry. 
     
     
         3 . The method of  claim 2 , wherein an end entry is identified as any entry that corresponds to a logout request. 
     
     
         4 . The method of  claim 2 , wherein an end entry for a client session is identified as any entry associated with that client session that has no other entries for that client session that occur within a session expiration window. 
     
     
         5 . The method of  claim 2 , wherein an end entry for a client session is identified as any entry having a first timestamp value, where the difference between first timestamp value and a second timestamp value associated with a subsequent entry in the subset of log files exceeds a timeout value. 
     
     
         6 . The method of  claim 1 , further comprising outputting all entries in the subset of log file entries that do not belong to a complete client session as raw log data. 
     
     
         7 . The method of  claim 1 , further comprising outputting as raw log data all entries in the subset of log file entries that belong to an incomplete client session which has a beginning entry but no end entry. 
     
     
         8 . An article of manufacture having at least one recordable medium having stored thereon executable instructions and data which, when executed by at least one processing device, cause the at least one processing device to:
 read a plurality of records from a file system into a ring buffer, where said plurality or records comprises a subset of all records in the file system;   scan each record in the ring buffer to identify a user session for said record and to identify any start or end records in the ring buffer;   allocate, for each identified user session, an index to identify all records in the ring buffer that are associated with the identified user session and to identify all start or end records; and   process the index to group all records in the ring buffer belonging to a complete user session, to output the grouped records for further analysis.   
     
     
         9 . The article of manufacture of  claim 8 , wherein the index comprises:
 a session record for each identified user session for keying into the ring buffer to identify log records associated with said identified user session;   a hash table for keying into the session record based upon session key information;   a linked listing of last seen log records for each session; and   a linked list of first seen log records for each session.   
     
     
         10 . The article of manufacture of  claim 8 , wherein the ring buffer implements a sliding window to process all of the log records in the file system into complete user sessions by sequentially adding and removing log records to the ring buffer until all of the log records in the file system have been processed. 
     
     
         11 . A system for session-based processing of log files using a data processing system and network session data collected from one or more users, the system comprising:
 a log file collection system for collecting a plurality of server request entries, wherein a server request entry comprises a session identifier; and   a processing engine to process at least a subset of the plurality of server request entries to group the server request entries by session using the session identifier in each server request entry.   
     
     
         12 . The system of  claim 11 , wherein the processing engine uses a plurality of data structures to group the web server request entries by session, said plurality of data structures comprising:
 a ring buffer for storing the subset of the plurality of web server request entries,   a per-session record for keying into the ring buffer   a hash table for keying into the per-session records   a linked list of last processed web server request entries for each session, and   a linked list of first processed web server request entries for each session.   
     
     
         13 . The system of  claim 11 , wherein the processing engine uses a sliding memory window to process the subset of the plurality of web server request entries. 
     
     
         14 . The system of  claim 11 , further comprising a parser for further analysis the web server request entries that have been grouped by session to generate a user session history. 
     
     
         15 . The system of  claim 11 , where the processing engine generates an output file containing web server request entries corresponding to one or more complete user sessions. 
     
     
         16 . The system of  claim 11 , where the processing engine generates an output file containing web server request entries corresponding to one or more incomplete user sessions. 
     
     
         17 . The system of  claim 11 , where the processing engine generates an output file containing web server request entries corresponding to one or more user sessions that do not include an end session entry. 
     
     
         18 . A system for parsing web site logs one session at a time, comprising:
 means for storing network session data from at least one server log file;   means for reading a subset of the network session data;   means for processing the subset of the network session data to group said network session data by session;   means for generating a first output file containing network session data grouped by session; and   means for parsing said first output file.   
     
     
         19 . The system of  claim 18 , wherein the means for reading a subset of the network session data comprises a sliding window. 
     
     
         20 . The system of  claim 18 ,-wherein the means for reading a subset of the network session data comprises a ring buffer.