Leak: materials, bindless texture slots and geometry of a sim you left are never freed

sky_line commented

2026-10-12 23:08:40 +00:00

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Measured (owner, 2026-10-12, RTX, plenty of VRAM): teleported from an event sim to home at 23:01:49 and sampled every 15 s.

	Event sim	Peak	Home, 3 min later
Objects	16,249	28,576	16,881 (old sim's objects gone by 23:02:53)
LL texture list	5,830	11,559	7,138 and falling (LL's 30 s flush works)
Material store	3,863	7,520	7,520 -- never shrinks
GPU texture slots (total_bindless)	4,818	9,601	9,601 -- never released
Texture VRAM	700 MB	1,243 MB	1,155 MB (barely moves)
Mesh slots	29,943	51,689	51,425 -- old sim's ~21.5k slots retained
Geometry VRAM	692 MB	823 MB	823 MB
CPU geometry mirror	472 MB	649 MB	646 MB

In a longer session that visited three sims, the material store reached 34,334 materials with ~18k objects loaded, and textures 53k.

Owner direction: free resources once they're no longer needed. Keeping a left sim's assets in VRAM for a possible return is not worth it: visiting several sims (especially during events) is the common pattern, and the stale data eats headroom and later forces bulk cleanup under pressure (the geometry GC thrash fixed earlier today was this).

Fix: release by liveness, not by memory pressure.

Materials: a material with no live instance referencing it is released (short grace, e.g. 30-60 s, to ride out LOD / re-ingest churn); its texture references drop.
Bindless texture slots / GPU images: freed when their texture / material is released (and when LL deletes the texture), so texture VRAM follows LL's list.
Geometry: mesh slots / LOD groups with no live instance are freed in the background (time-sliced), with the CPU mirror following; the GC budget stays as the pressure backstop, not the only path.
Correctness: refcounts / liveness must be exact (no freeing something a live or pending object uses; re-ingest re-acquires cleanly); budgeted per frame; stats: released per minute by kind, live counts, and a log line on teleport summarizing what was freed within a minute.
Verification: repeat the TP test -- after leaving a sim, materials, bindless slots, mesh slots, geometry VRAM and the CPU mirror return close to the new sim's own working set within ~1-2 minutes.

**Measured (owner, 2026-10-12, RTX, plenty of VRAM):** teleported from an event sim to home at 23:01:49 and sampled every 15 s. | | Event sim | Peak | Home, 3 min later | |---|---|---|---| | Objects | 16,249 | 28,576 | 16,881 (old sim's objects gone by 23:02:53) | | LL texture list | 5,830 | 11,559 | 7,138 and falling (LL's 30 s flush works) | | **Material store** | 3,863 | 7,520 | **7,520 -- never shrinks** | | **GPU texture slots (total_bindless)** | 4,818 | 9,601 | **9,601 -- never released** | | Texture VRAM | 700 MB | 1,243 MB | 1,155 MB (barely moves) | | **Mesh slots** | 29,943 | 51,689 | **51,425 -- old sim's ~21.5k slots retained** | | **Geometry VRAM** | 692 MB | 823 MB | **823 MB** | | **CPU geometry mirror** | 472 MB | 649 MB | **646 MB** | In a longer session that visited three sims, the material store reached 34,334 materials with ~18k objects loaded, and textures 53k. **Owner direction:** free resources once they're no longer needed. Keeping a left sim's assets in VRAM for a possible return is not worth it: visiting several sims (especially during events) is the common pattern, and the stale data eats headroom and later forces bulk cleanup under pressure (the geometry GC thrash fixed earlier today was this). **Fix:** release by liveness, not by memory pressure. - **Materials:** a material with no live instance referencing it is released (short grace, e.g. 30-60 s, to ride out LOD / re-ingest churn); its texture references drop. - **Bindless texture slots / GPU images:** freed when their texture / material is released (and when LL deletes the texture), so texture VRAM follows LL's list. - **Geometry:** mesh slots / LOD groups with no live instance are freed in the background (time-sliced), with the CPU mirror following; the GC budget stays as the pressure backstop, not the only path. - **Correctness:** refcounts / liveness must be exact (no freeing something a live or pending object uses; re-ingest re-acquires cleanly); budgeted per frame; stats: released per minute by kind, live counts, and a log line on teleport summarizing what was freed within a minute. - **Verification:** repeat the TP test -- after leaving a sim, materials, bindless slots, mesh slots, geometry VRAM and the CPU mirror return close to the new sim's own working set within ~1-2 minutes.

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2026-10-12 23:08:40 +00:00

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2026-10-12 23:08:40 +00:00

sky_line commented

2026-10-12 23:21:37 +00:00

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20 minutes after the teleport (23:21), nothing further was released: materials 7,520, bindless slots 9,601, mesh slots 51,425, geometry VRAM 823 MB, CPU mirror 646 MB, texture VRAM 1,156 MB. LL texture list levelled off at 7,135 (from a peak of 11,559). So the retention is permanent, not slow.

sky_line commented

2026-10-12 23:47:51 +00:00

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Fix verified (build 70d807f1ea, pushed to main): home -> another sim -> home round trip.

	home, fresh login	24 s after return	3 min after return	before fix
mesh slots	23,369	45,239	24,215	51,425
geometry buffers	347 MB	~908 MB	331 MB	823 MB
CPU mirror	207 MB	649 MB	225 MB	646 MB
materials (live)	5,600	8,753	5,288	5,380
texture slots	5,904	10,313	5,863	~5,970

released since TP: geometry 1,232 MB, mirror 461 MB, 24.6k mesh slots, 5,475 materials, 4,825 texture images. Two liveness compactions shrank the buffers 594 -> 331 MB; no hitches logged after the return. Orphan rows 0 throughout.

Correction to my earlier comment: the materials= / total_bindless= figures were high-water marks (ids are reused); the live counts were already falling. Geometry was the real leak (GC only ran above a ~2.5 GB budget). Those log fields now print live (hw).

Tradeoff: after more than 30 s away (RenderVKAssetReleaseGraceSec), a sim's assets are released and reload on return.

Fix verified (build 70d807f1ea, pushed to main): home -> another sim -> home round trip. | | home, fresh login | 24 s after return | 3 min after return | before fix | |---|---|---|---|---| | mesh slots | 23,369 | 45,239 | **24,215** | 51,425 | | geometry buffers | 347 MB | ~908 MB | **331 MB** | 823 MB | | CPU mirror | 207 MB | 649 MB | **225 MB** | 646 MB | | materials (live) | 5,600 | 8,753 | **5,288** | 5,380 | | texture slots | 5,904 | 10,313 | **5,863** | ~5,970 | `released since TP`: geometry 1,232 MB, mirror 461 MB, 24.6k mesh slots, 5,475 materials, 4,825 texture images. Two liveness compactions shrank the buffers 594 -> 331 MB; no hitches logged after the return. Orphan rows 0 throughout. Correction to my earlier comment: the `materials=` / `total_bindless=` figures were high-water marks (ids are reused); the live counts were already falling. Geometry was the real leak (GC only ran above a ~2.5 GB budget). Those log fields now print live (hw). Tradeoff: after more than 30 s away (`RenderVKAssetReleaseGraceSec`), a sim's assets are released and reload on return.

sky_line referenced this issue from a commit

2026-10-12 23:47:51 +00:00

Asset lifetime by liveness: geometry, materials, release stats (#737)

sky_line referenced this issue from a commit

2026-10-12 23:47:51 +00:00

Asset lifetime: grace floors for geometry, texture eviction in wall time (#737)

sky_line referenced this issue from a commit

2026-10-12 23:47:51 +00:00

Merge #737: asset lifetime by liveness

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2026-10-12 23:47:51 +00:00

sky_line commented

2026-10-14 06:33:44 +00:00

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Shipped in 1.3.0 Beta 8 (70d807f1ea asset lifetime by liveness; fix verified by round-trip test in the comments). Closing -- reopen or comment if you still see this.

Shipped in 1.3.0 Beta 8 (70d807f1ea asset lifetime by liveness; fix verified by round-trip test in the comments). Closing -- reopen or comment if you still see this.

sky_line

2026-10-14 06:33:45 +00:00

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Leak: materials, bindless texture slots and geometry of a sim you left are never freed #737