> For the complete documentation index, see [llms.txt](https://codifi-fdm.gitbook.io/codifi-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://codifi-fdm.gitbook.io/codifi-docs/known-issues-and-edge-cases/known-issues/raster-overlays-crash-or-fill-storage.md).

# Projects with several raster overlays crash the app or fill device storage

### Symptom

On a Project carrying several raster overlays, the app closed shortly after the Project map opened. Crews reported the map loading "about four or five topos" and then the app shutting down, too quickly to close anything first.

Separately, these Projects consumed far more device storage than the size of the uploaded files suggested. A set of raster uploads totaling under 20 MB could occupy several hundred megabytes once on the device.

Reproduced in the field on a Project carrying eight USGS 7.5-minute topo quads plus a shaded relief layer.

### Why this happens

**The crash** was a rendering problem rather than a download problem. The download completed successfully; the app died as the map drew. Opening at Project extent meant every raster was inside the viewport at once, so all of their tiles mounted simultaneously with no zoom threshold and no ceiling on how many could be held in memory. A single full quad decodes to well over a hundred megabytes, so four of them was enough to exhaust the device.

**The storage cost** came from how tiles were encoded. Scanned topographic maps arrive with a small color palette, which is why they compress so well. Tiles were being written out in a much heavier format that discarded that advantage, inflating the same imagery many times over.

### Workaround

No longer required. While the issue was open, crews were advised to switch rasters off from the map layers sheet and enable only the one covering their current work area.

### Resolution

Fixed in **v3.3**:

* **A zoom threshold.** Raster tiles no longer mount below a working zoom level, so opening a Project at full extent no longer tries to draw everything.
* **A tile ceiling.** The number of tiles held in memory at once is bounded.
* **A fixed draw order.** Raster imagery is pinned beneath vector Overlays and your Records, so the stack renders the same way every time.
* [**Coverage footprints**](/codifi-docs/mobile-app/mapping-locations/map-overlays.md)**.** A raster can show a labeled outline of the ground it covers without loading its imagery, so crews can tell which sheet to switch on.
* **Smaller tiles.** Tile encoding was changed so palette-based imagery keeps its compression, substantially reducing what a raster occupies on the device.

{% hint style="info" %}
**Still worth being deliberate.** The guards make a heavy Project safe to open, but several overlapping high-resolution rasters remain demanding. Keep one or two on at a time, and set sensible default visibility from the web app so crews open the Project with a workable starting set.
{% endhint %}

### Related

* [Map Overlays](/codifi-docs/mobile-app/mapping-locations/map-overlays.md)
* [Adding Map Overlays](/codifi-docs/web-app/map-setup-and-offline-areas/map-overlays/adding-map-overlays.md)

### Internal notes

CP-6097 (crash and load guards), CP-6098 (labeled footprints), CP-6099 (tile size inflation in the overlays Lambda).