Snapshots

## Snapshots |

| Here you can configure how the heap dump analysis is saved for snapshots. Most of the time spent when loading snapshots is for the analysis of the raw data, the removal of unreferenced objects and the retained size calculation. JProfiler stores the result of this analysis next to the snapshot if possible. This means that opening a snapshot that has already been analyzed is orders of magnitudes faster if a saved heap dump analysis can be found. If the heap dump analysis takes up a too much disk space, you can switch off the heap dump analysis saving altogether on this tab. The analysis will then be created each time you open the snapshot. In general, if a heap dump analysis is missing or incorrect (e.g. from a different snapshot) it will simply be recreated.

| The default storage format for the heap dump analysis is directory-based, e.g. if your snapshot is saved to `snapshot.jps`, the analysis is stored in the directory `snapshot.jps.analysis`. In that directory there are multiple files and further subdirectories that contain the entire analysis. If this is not practical for some reason, you can choose the `TAR archive` or `Compressed TAR archive` options on this tab. Both of them make moving snapshots together with their analysis to a different computer easier since you only have one additional file. The compressed tar archive option is noticeably slower than the alternatives, but takes up less disk space.

| Snapshots taken with offline profiling do not have an existing heap analysis. If you're taking these snapshots in an automated fashion, you can use the command line tool "jpanalyze" or the corresponding "analyze" ant task in order to massively speed up the opening of these snapshot in the JProfiler GUI.