Building a map cache can speed up common ArcMap tasks such as drawing, selecting, labeling, and editing features. The map cache holds the features in the current map extent in memory on your local machine. A map cache results in faster processing because ArcMap doesn't have to retrieve data from the server every time you update your display.
Care must be taken, though, when using map caches to edit in nonversioned edit sessions. After you build a map cache of some data, if another user edits that data, you will no longer be working with data that is correct. When you commit, it is possible to overwrite the other user's edits. The following sequence of events provides an example of how this can happen.
Tom starts editing, builds a map cache of well points, and displays the points in ArcMap.
Susan starts her own edit session, moves a well point, and commits the change.
Tom built his map cache before Susan started editing so at this point Tom still sees the well point in its original location. Tom moves the well point to yet another location and commits, overwriting Susan's edits.
