[Bug] GTAV Enhanced: selective base-map RPF removal crashes

[uguranlar]

Summary

Hotfix 5 fixed the resource-backed images.meta path crash reported in #124. However, there is still no safe way to prevent selected Los Santos RPF archives from being mounted.

When the relevant RPF entries are removed from images.meta, even with an otherwise valid and carefully reduced configuration, the client crashes during startup. As a result, developers are forced to keep those archives mounted and override thousands of individual YMAP and YBN files with empty replacements.

This is not a practical or reliable solution. The core issue is that selectively dismounting unnecessary Los Santos RPF archives currently results in a client CTD instead of being supported or producing a clear dependency error.

Issue type

Client

Repro rate

Always

Server build version

b101

OS

Windows 11 Pro 10.0.26200

CPU

AMD Ryzen 5 7500F 6-Core Processor

GPU

NVIDIA GeForce RTX 5070 Ti

RAM

32 GB

Storage type

SSD NVMe

Connection type

None

ISP and bandwidth

No response

DxDiag

No response

Network graph

No response

Platform

Windows

OS version / distribution

Windows 11 Pro 10.0.26200

CPU

AMD Ryzen 5 7500F 6-Core Processor

RAM

32 GB

Using txAdmin?

Yes

Hosting provider

Self-hosted

Machine type

Dedicated

/perf endpoint output

No response

DDoS protection

No

ulimit -n value (Linux only)

No response

Docker Compose file (Docker only)

No response

Steps to Reproduce

1. Use FiveM for GTAV Enhanced with game cache gamecache_gen9/1158_13, OneSync enabled and a b101 server artifact.
2. Create a resource containing the current stock Enhanced gta5.meta and images.meta, loaded with replace_level_meta 'gta5'. After Hotfix 5, a byte-identical resource-backed copy loads successfully.
3. Keep the XML structure valid but remove all <Item> archive entries from images.meta. Fully restart the server and connect. The Enhanced client crashes instead of reporting missing mandatory archive dependencies.
4. Restore the 96-entry working list. Remove the eight RPF entries that contain the remaining native YMAPs (96 -> 88 entries), then test both with no YMAP proxies and with 981 blank YMAP proxies. In both cases the client crashes during map reload before the connection marker.
5. Restore the 96-entry list. As the fallback, stream filename replacements for the base map: 10,488 blank YMAPs and 11,753 valid 10 cm YBN proxy bounds placed far outside the playable area.
6. Load a custom map containing 41 real custom YBN collision files. Verify the custom collision in game.
7. With the 11,753 YBN proxies enabled, most custom collision does not work, even though the custom YBNs are present in the client cache with correct sizes/hashes and there are no filename collisions.
8. Disable only the 11,753 proxy YBNs, fully restart and reconnect. The custom-map collision starts working again.

Expected Behavior

FiveM should provide a supported and deterministic way to exclude selected Los Santos/base-map RPF entries before map initialization while preserving mandatory base-game archives and GTA Online DLC such as mpheist4.

If a reduced mount graph is invalid, the client should reject it with a clear validation error naming the missing archive/dependency instead of crashing. Removing the base map should not require streaming more than 22,000 proxy files, and proxy files should not prevent unrelated custom collision from working.

Actual Behavior

A valid but empty images.meta causes a client CTD. Aggressively reduced lists can either crash during map reload or pass connection tests and later crash during city traversal.

Using disabled=true does not unmount archives that were already loaded. RemoveIpl only handles IPL/YMAP instances and does not remove collision, path nodes, navmeshes or every archetype registration.

The remaining workaround is thousands of streamed filename replacements. In a controlled A/B test, enabling 11,753 YBN proxies caused widespread loss of custom-map collision; disabling only those proxies restored it.

Evidence

Previous resource-backed path crash, opened by us and fixed in Hotfix 5:
#124

Controlled metadata reduction:

• Working reduced images.meta baseline: 96 RPF entries.
• Eight remaining YMAP-carrying RPF entries removed: 96 -> 88.
• 88 entries with zero overrides: generic client crash during map reload.
• 88 entries with 981 blank YMAP overrides: same client crash.
• Removing 93/94 PERMANENT_ITYP_FILE entries did not eliminate the traversal crash.
• Reproduced on the 28-point city route near Pillbox on b98 and b101:
  [ASSERT]: 0x43ED4D14 Pool Full, Size == 3000

Filename-replacement fallback:

• 10,488 YMAP proxies.
• 11,753 YBN proxies.
• 41 real custom-map YBNs.
• No proxy/custom YBN filename collisions.
• Custom YBN files reached the Enhanced client cache with correct hashes and sizes.
• A/B result: proxy YBNs enabled = most custom collision absent; only proxy YBNs disabled = custom collision restored.

The current session log confirms that b101 is installed and b110 is now available. The reproduction above records the builds on which the controlled tests were performed.

Additional Context

This is a total-conversion map use case. The custom map supplies its own YMAPs, YBN collisions, YND path nodes, YNV navmeshes, YTYP archetypes, models and textures.

We need to remove Los Santos map archives while preserving:

• GTA Online DLC content, including mpheist4
• weather, sky and timecycle systems
• water
• required distant-light and heightmap data
• audio, characters, vehicles and other non-map assets

Re-streaming DLC is not a production solution because clients already own the files, it requires gigabytes of downloads, and streamed MLO/archetype dependencies are less stable.

A suitable solution could be a resource-manifest denylist/unmount directive processed before INIT_SESSION, or equivalent replace_level_meta semantics that actually exclude selected logical archive entries before they mount. It should preserve mount order, restore stock mounts when the resource stops, and report found/removed/missing entries.

An entirely empty archive graph is not expected to be playable. The empty-list test demonstrates the lack of dependency validation and the CTD failure mode. The actual request is supported selective base-map archive removal while mandatory and DLC archives remain mounted.

Related pool reports:
#299
#110
#72
#155
#18

[uguranlar]

I want to emphasize why this is more than an edge-case request or a convenience feature.

This blocks serious total-conversion work from being deployed reliably. It also creates unnecessary client downloads, resource enumeration overhead, cache pressure, longer development iteration times and failures that are extremely difficult to diagnose.

At the moment, there is no production-safe path for doing this on GTAV Enhanced (Not on legacy too but i already migrated to enhanced so)

I would also like to mention the following resource:

https://forum.cfx.re/t/release-los-santos-removed-empty-game-map-compatible-with-ipl-loaders/5176084

This resource previously relied on preventing the relevant RPF archives from being mounted. However, after an update to the Legacy version, that method stopped working, forcing the developer to replace the original files with empty placeholder files instead.

While this workaround can still remove the Los Santos map, overriding thousands of individual files is far from optimal. It increases pool usage, contributes to stuttering and longer loading times, adds unnecessary streaming and cache overhead, and may cause conflicts with custom assets.

The fact that a widely used resource had to move from archive-level mount control to mass file replacement demonstrates why a properly supported RPF exclusion mechanism is needed.

Thank you for taking the time to review this. I appreciate the work that goes into maintaining the platform, and I hope this issue can be considered for a proper supported solution.

[uguranlar]

Just bumping this as the issue is still reproducible on the latest Enhanced build and remains a major blocker for custom map projects.

[uguranlar]

Bumping this once more as this is still a major blocker for total-conversion/custom map projects on Enhanced.

The current workaround still requires mass file replacement, which introduces significant streaming, cache and pool overhead instead of solving the problem at the archive mount level.

If useful, I can provide an updated minimal reproduction, logs, or run additional tests against the current build. Would appreciate any indication whether selective RPF exclusion/unmounting is something that could be supported or investigated.