About Managing Frames
You can set preferences to create frames for workspace operations that affect the cache. You can also specify the number of frames to be retained as they occupy significant disk space. No server-based tasks can automatically remove or permanently purge frames unless the number of frames exceeds the limit set as the preference. When the number of frames you specify reaches the limit set as the preference, old frames are automatically invalidated and removed to accommodate new frames. Locked frames are not removed automatically.
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You are not warned when frames are automatically invalidated and removed when they exceed the limit set as the preference. Therefore, you must set a high limit as the preference or lock the frames that you want to retain.
When you purge frames, locally cached objects associated with the purged frames are subject to cache limit management. You cannot delete or purge locked frames. The deletion of frames only invalidates the local cache without deleting it, but the deletion of Workspace removes all the frames and cached contents in the workspace. You can lock frames to prevent them from being accidentally purged. However, you cannot lock the frame associated to the current state of the workspace because the Event Manager does not list the current frame.
As frames are dependent on the Event Manager for information, events are persistent across multiple Creo sessions. Frames are preserved across sessions and frame information is written to a log file. If you are working offline or if the workspace is portable, frames are not created when the workspace is connected to a non-Creo CAD system.