Loupe Session File Format

As the Loupe Agent runs it records all of the log messages, metrics, and other related information into a Loupe Session File which is written to local storage on each computer where the application is run.  This file is in a binary, highly compressed format that supports storing structured data in native types regardless of platform.  It supports versioning, allowing new data elements to be added while preserving backwards compatibility.  In general a Loupe Session File is approximately 1/10th the size of a text file containing the same log messages and yet it contains significant additional data not present in a normal log file.

Where Session Files are Stored

By default this data is stored in a subdirectory of the Common Application Data folder.  This varies by operating system, for example:

• Windows XP / Server 2003: C:\Documents and Settings\All Users\Application Data\Gibraltar\Local Logs
• Windows Vista / 7 / Server 2008:  C:\ProgramData\Gibraltar\Local Logs

This folder is designed for data that has to be readable and writable by all local users.  When the Loupe Agent first creates the folder structure it ensures that the right permissions are assigned and verifies that the current user can create files, delete files, and write to files in the directory.  If not, it will revert to the user's personal local application data directory for the current session.

Recording to an Alternate Folder

We recommend that you let session files be stored in the default folder.  This keeps the session files, the Loupe Index, and other working files in the same directory.  However, you can freely choose to store your data files in an alternate directory by setting the folder option in Developer's Guide - Session File Configuration.  We recommend that you still select a folder that's within the Common Application Data folder for the current operating system.  If you specify a folder the Agent will verify that the current user has sufficient permissions to use this directory.  If not, it will revert to the default path as described above.

Managing Disk Space

The Loupe Agent will automatically get rid of session files in two circumstances:

1. Session File Pruning:  By default a disk quota is configured for the total number of MB of session data for a given application and the retention period.  See Developer's Guide - Session File Pruning for full details.
2. Auto Prune on Send:  If you have configured automatic session file transmission to the Loupe Server it can be set to delete local session files as soon as they are confirmed by the Server.  See Loupe Server - Automatically Sending Session Data for full details.

Disabling Session Files

You can disable the session file recording of the agent while leaving the rest of the agent operable.  In this mode the Live Viewer features are still available but since no session file is recorded there is no data to send to the Server or the Packager.