[viewer] Low FPS with RT Shadows #1085

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opened 2026-10-25 21:22:35 +00:00 by slipstream-reports · 1 comment

slipstream-reports commented

2026-10-25 21:22:35 +00:00

Collaborator

Source: in-viewer report (Help > Report Bug)

Reporter (avatar name as given; not verified):

Financial Rizzler

System

Version: 1.5.0.1
Channel: Slipstream Beta
OS: Linux 7.2.9-ogc3.1.fc44.x86_64 #1 SMP PREEMPT_DYNAMIC Mon Oct 12 22:17:26 UTC 2026 x86_64
CPU: AMD Ryzen 7 5700X 8-Core Processor (4665.84 MHz)
Memory: 15897 MB
GPU: AMD Radeon RX 9070 XT (RADV GFX1201)
GPU driver: radv Mesa 26.2.5 (git-ddaf85e353)
Vulkan: 1.4.354; ray tracing: enabled
Window: 1920x1006
Grid: Second Life Main Grid (Agni)
Region: Renegade Nebula
Display: swapchain 1920x1006 BGRA8/sRGB fifo x4 (30 MB); monitors 1, window on 1920x1080@75Hz scale 1.00, HDR off
VRAM: used 4349/13220 MB (cap auto, OS 14695, reserve 1469) tracked 4123 fixed 1326 slack 244 swap 30 ovh 196 (unattributed 195) room 11893 | ladder 0/45
VRAM by category: tex 1255 geom 234 scene 136 cull 57 targets 546 probes 207 shadow 165 rt-as 525 rt-aux 154 rt-mask 103 staging 1 part 68 ui 147 upscale 146 texenc 86 rig 110
VRAM overhead: ovh 196 MB = pad 0 (823 allocs @4K) + driver 0 [] + untracked 0 + ? 195; min 11; slack vram 244 sys 248
Texture pools: tex pools 223 blocks 954 MB, 3176 images 771 MB live (81% occupied), slack 183 (free 129 + rounding 54); medium classes 790 MB 81% stranded 93, fallback 152 MB 83% stranded 25 (images hit/miss 13083/8
Host memory: host-visible 330 MB / 112 allocs [scene 0/3 cull 1/10 targets 0/2 rt-aux 15/16 rt-mask 1/2 staging 297/40 readback 8/19 part 4/16 ui 4/2 upscale 0/1 texenc 0/1] device-only 4123 MB | /s: alloc hv 0.0
Pipeline compiles: async 318/237 51.9s +3786MB t15 c10 ob0: mRtFwdPipe (DeferRtFwd) (DeferRtFwd) 32.5s 182M c7; mRtTracePipe (DeferRtTrace) (DeferRtTrace) 32.2s 342M c7; mRtTraceListPipe (DeferRtTraceList) (DeferRtTrace
Settings:
  RenderDeferredSSAO = 1
  RenderDepthOfField = 0
  RenderFPSLimit = 0
  RenderFSAAType = 2
  RenderFarClip = 256
  RenderHiDPI = 0
  RenderMaxTextureResolution = 2048
  RenderMaxVideoMemoryMB = 0
  RenderMirrors = 0
  RenderQualityPerformance = 6
  RenderReflectionProbeCount = 256
  RenderReflectionProbeDetail = 1
  RenderReflectionProbeLevel = 3
  RenderReflectionProbeResolution = 128
  RenderScreenSpaceReflections = true
  RenderShadowDetail = 2
  RenderTransparentWater = 1
  RenderVKAOStandard = 1
  RenderVKAlphaShadingRate = 0
  RenderVKDlssRayReconstruction = 2
  RenderVKFramePacing = 1
  RenderVKGodRays = 3
  RenderVKNoVsyncPresentMode = 0
  RenderVKOpaqueShadingRate = 0
  RenderVKPipelineCompileBudgetMB = 0
  RenderVKPipelineCompileThreads = 0
  RenderVKProjectorShadows = 2
  RenderVKRayTracing = 1
  RenderVKRenderScale = 1
  RenderVKShadowResolution = 256
  RenderVKSunShadows = 2
  RenderVKTAA = 0
  RenderVKTextureCompression = 4
  RenderVKUpscaler = 1
  RenderVSyncEnable = 1
  RenderVolumeLODFactor = 8
  SlipstreamRenderTonemapType = 2
  UIScaleFactor = 1
  VKDebugForceIntelCompileCap = 0

Description

(Linked to #1080)
Low FPS with RT Shadows enabled, set to Half Resolution, low quality, and performance updates.

Steps to reproduce

not given

Log excerpt

Full scrubbed excerpt: slipstream-log-excerpt.txt

Last 40 lines

    0.172   0.157   0.248   0.374          vk_rtBuild
    0.241   0.063   0.096   3.700        rw_ensureTargets
    0.196   0.150   0.568   0.805        rw_buildRigged
    0.077   0.071   0.111   0.148          vk_animBuild
    0.071   0.068   0.085   0.104        ws_lights
    0.900   0.734   2.097   2.351      vk_uiBuild
    0.754   0.571   1.947   2.219        Interface drawing (ui_draw)
    0.126   0.118   0.168   0.203        Name tags / hover text (vk_hudText)
    0.792   0.749   0.995   1.241      vk_submit
    0.696   0.600   1.139   1.199      Scene sync to the GPU (vk_syncFromStores)
    0.695   0.600   1.138   1.199        vk_sync_total
    0.459   0.558   0.993   1.086          vk_texResLap
    0.234   0.000   1.113   1.158          vk_texUpload
    0.141   0.135   0.176   0.226      vk_uiRecord
    0.249   0.241   0.308   0.373    Scene build for the GPU (buildWorldFrame)
    0.097   0.094   0.124   0.145      Light collection (bwf_lights)
    1.320   1.251   1.793   2.210  World update (LL_idle_total)
    0.752   0.661   1.228   1.714    New object processing (vk_ingestTick)
    0.280   0.242   0.494   0.551      ing_priority
    0.277   0.226   0.725   0.827      sweep_total
    0.078   0.069   0.122   0.236        moveQueue
    0.184   0.166   0.216   0.363      ing_gc
    0.171   0.165   0.214   0.258        vk_orphanAudit
    0.439   0.405   0.640   0.776    Object updates (LL_objectListUpdate)
    0.401   0.368   0.603   0.730      objUpd_av
    0.261   0.253   0.326   0.397        avatarCharacter
    0.073   0.029   0.231   0.287        av_misc
    0.149   0.143   0.186   0.278    Interface update (LL_updateUI)
    0.135   0.068   0.481   0.555    Idle callbacks (LL_idleCallbacks)
    0.115   0.112   0.153   0.173    Texture updates (LL_updateImages)
    0.107   0.104   0.127   0.145    ui_upd_rest
    0.106   0.084   0.211   0.280    Network messages (LL_idleNetwork)
    0.105   0.102   0.140   0.154    LL_texFetch
    0.462   0.506   0.531   0.545  vk_texResScan
    0.060   0.054   0.077   0.088  vk_rtP_record
    0.050   0.036   0.110   0.122  vk_texP_trickle
    0.038   0.036   0.050   0.068  vk_rtP_feedback
    0.035   0.034   0.045   0.054  vk_rtP_terrain
    0.025   0.024   0.032   0.041  Input (df_gatherInput)
    0.022   0.004   0.118   0.353  vk_texP_setup

Screenshot

_{Filed by the Slipstream report relay. The reporter's identity is not verified; system details are as sent by the reporter.}

**Source:** in-viewer report (Help > Report Bug) **Reporter** (avatar name as given; not verified): ~~~text Financial Rizzler ~~~ ### System ~~~text Version: 1.5.0.1 Channel: Slipstream Beta OS: Linux 7.2.9-ogc3.1.fc44.x86_64 #1 SMP PREEMPT_DYNAMIC Mon Oct 12 22:17:26 UTC 2026 x86_64 CPU: AMD Ryzen 7 5700X 8-Core Processor (4665.84 MHz) Memory: 15897 MB GPU: AMD Radeon RX 9070 XT (RADV GFX1201) GPU driver: radv Mesa 26.2.5 (git-ddaf85e353) Vulkan: 1.4.354; ray tracing: enabled Window: 1920x1006 Grid: Second Life Main Grid (Agni) Region: Renegade Nebula Display: swapchain 1920x1006 BGRA8/sRGB fifo x4 (30 MB); monitors 1, window on 1920x1080@75Hz scale 1.00, HDR off VRAM: used 4349/13220 MB (cap auto, OS 14695, reserve 1469) tracked 4123 fixed 1326 slack 244 swap 30 ovh 196 (unattributed 195) room 11893 | ladder 0/45 VRAM by category: tex 1255 geom 234 scene 136 cull 57 targets 546 probes 207 shadow 165 rt-as 525 rt-aux 154 rt-mask 103 staging 1 part 68 ui 147 upscale 146 texenc 86 rig 110 VRAM overhead: ovh 196 MB = pad 0 (823 allocs @4K) + driver 0 [] + untracked 0 + ? 195; min 11; slack vram 244 sys 248 Texture pools: tex pools 223 blocks 954 MB, 3176 images 771 MB live (81% occupied), slack 183 (free 129 + rounding 54); medium classes 790 MB 81% stranded 93, fallback 152 MB 83% stranded 25 (images hit/miss 13083/8 Host memory: host-visible 330 MB / 112 allocs [scene 0/3 cull 1/10 targets 0/2 rt-aux 15/16 rt-mask 1/2 staging 297/40 readback 8/19 part 4/16 ui 4/2 upscale 0/1 texenc 0/1] device-only 4123 MB | /s: alloc hv 0.0 Pipeline compiles: async 318/237 51.9s +3786MB t15 c10 ob0: mRtFwdPipe (DeferRtFwd) (DeferRtFwd) 32.5s 182M c7; mRtTracePipe (DeferRtTrace) (DeferRtTrace) 32.2s 342M c7; mRtTraceListPipe (DeferRtTraceList) (DeferRtTrace Settings: RenderDeferredSSAO = 1 RenderDepthOfField = 0 RenderFPSLimit = 0 RenderFSAAType = 2 RenderFarClip = 256 RenderHiDPI = 0 RenderMaxTextureResolution = 2048 RenderMaxVideoMemoryMB = 0 RenderMirrors = 0 RenderQualityPerformance = 6 RenderReflectionProbeCount = 256 RenderReflectionProbeDetail = 1 RenderReflectionProbeLevel = 3 RenderReflectionProbeResolution = 128 RenderScreenSpaceReflections = true RenderShadowDetail = 2 RenderTransparentWater = 1 RenderVKAOStandard = 1 RenderVKAlphaShadingRate = 0 RenderVKDlssRayReconstruction = 2 RenderVKFramePacing = 1 RenderVKGodRays = 3 RenderVKNoVsyncPresentMode = 0 RenderVKOpaqueShadingRate = 0 RenderVKPipelineCompileBudgetMB = 0 RenderVKPipelineCompileThreads = 0 RenderVKProjectorShadows = 2 RenderVKRayTracing = 1 RenderVKRenderScale = 1 RenderVKShadowResolution = 256 RenderVKSunShadows = 2 RenderVKTAA = 0 RenderVKTextureCompression = 4 RenderVKUpscaler = 1 RenderVSyncEnable = 1 RenderVolumeLODFactor = 8 SlipstreamRenderTonemapType = 2 UIScaleFactor = 1 VKDebugForceIntelCompileCap = 0 ~~~ ### Description ~~~text (Linked to #1080) Low FPS with RT Shadows enabled, set to Half Resolution, low quality, and performance updates. ~~~ ### Steps to reproduce _not given_ ### Log excerpt Full scrubbed excerpt: [slipstream-log-excerpt.txt](https://git.slipstreamviewer.org/attachments/15ea7327-f245-414e-9f77-4fc4d2768b57) <details><summary>Last 40 lines</summary> ~~~log 0.172 0.157 0.248 0.374 vk_rtBuild 0.241 0.063 0.096 3.700 rw_ensureTargets 0.196 0.150 0.568 0.805 rw_buildRigged 0.077 0.071 0.111 0.148 vk_animBuild 0.071 0.068 0.085 0.104 ws_lights 0.900 0.734 2.097 2.351 vk_uiBuild 0.754 0.571 1.947 2.219 Interface drawing (ui_draw) 0.126 0.118 0.168 0.203 Name tags / hover text (vk_hudText) 0.792 0.749 0.995 1.241 vk_submit 0.696 0.600 1.139 1.199 Scene sync to the GPU (vk_syncFromStores) 0.695 0.600 1.138 1.199 vk_sync_total 0.459 0.558 0.993 1.086 vk_texResLap 0.234 0.000 1.113 1.158 vk_texUpload 0.141 0.135 0.176 0.226 vk_uiRecord 0.249 0.241 0.308 0.373 Scene build for the GPU (buildWorldFrame) 0.097 0.094 0.124 0.145 Light collection (bwf_lights) 1.320 1.251 1.793 2.210 World update (LL_idle_total) 0.752 0.661 1.228 1.714 New object processing (vk_ingestTick) 0.280 0.242 0.494 0.551 ing_priority 0.277 0.226 0.725 0.827 sweep_total 0.078 0.069 0.122 0.236 moveQueue 0.184 0.166 0.216 0.363 ing_gc 0.171 0.165 0.214 0.258 vk_orphanAudit 0.439 0.405 0.640 0.776 Object updates (LL_objectListUpdate) 0.401 0.368 0.603 0.730 objUpd_av 0.261 0.253 0.326 0.397 avatarCharacter 0.073 0.029 0.231 0.287 av_misc 0.149 0.143 0.186 0.278 Interface update (LL_updateUI) 0.135 0.068 0.481 0.555 Idle callbacks (LL_idleCallbacks) 0.115 0.112 0.153 0.173 Texture updates (LL_updateImages) 0.107 0.104 0.127 0.145 ui_upd_rest 0.106 0.084 0.211 0.280 Network messages (LL_idleNetwork) 0.105 0.102 0.140 0.154 LL_texFetch 0.462 0.506 0.531 0.545 vk_texResScan 0.060 0.054 0.077 0.088 vk_rtP_record 0.050 0.036 0.110 0.122 vk_texP_trickle 0.038 0.036 0.050 0.068 vk_rtP_feedback 0.035 0.034 0.045 0.054 vk_rtP_terrain 0.025 0.024 0.032 0.041 Input (df_gatherInput) 0.022 0.004 0.118 0.353 vk_texP_setup ~~~ </details> ### Screenshot ![screenshot](https://git.slipstreamviewer.org/attachments/62154a98-1187-4f47-8b39-760afbf8f22b) --- <sub>Filed by the Slipstream report relay. The reporter's identity is not verified; system details are as sent by the reporter.</sub>

slipstream-log-excerpt.txt

202 KiB

screenshot.jpg

298 KiB

slipstream-reports added the

from-viewer

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labels

2026-10-25 21:22:35 +00:00

slipstream-reports added this to the Slipstream project

2026-10-25 21:22:35 +00:00

sky_line commented

2026-10-25 22:28:26 +00:00

Owner

Thanks for the report and the performance capture -- it's very useful.

What it shows: the frame is limited by the graphics card (about 35 ms per frame), and the ray-traced shadows alone take about 10 ms per frame on your RX 9070 XT, even at half resolution and low quality; ray-traced volumetric light (god rays) adds about 5 ms more. That is far more than we see on NVIDIA cards, so we're looking at how our shadow rays behave on AMD's ray tracing hardware specifically.

Two more captures would help a lot (Help > Report Bug after each, or attach the performance capture), in the same spot:

With the debug setting RenderVKAsyncCompute = 0 (Advanced > Debug Settings), everything else unchanged. This gives exact per-pass timings (with it on, some passes' timings include time spent waiting for the ray tracing).
With sun shadows ray-traced but projector shadows off (Preferences > Graphics > Advanced > Shadows), to see which part costs the most.

If you know whether the place you tested has a lot of alpha-masked objects (foliage, fences, hair, lace), that's helpful too.

Thanks for the report and the performance capture -- it's very useful. What it shows: the frame is limited by the graphics card (about 35 ms per frame), and the ray-traced shadows alone take about **10 ms** per frame on your RX 9070 XT, even at half resolution and low quality; ray-traced volumetric light (god rays) adds about 5 ms more. That is far more than we see on NVIDIA cards, so we're looking at how our shadow rays behave on AMD's ray tracing hardware specifically. Two more captures would help a lot (Help > Report Bug after each, or attach the performance capture), in the same spot: 1. With the debug setting **`RenderVKAsyncCompute` = 0** (Advanced > Debug Settings), everything else unchanged. This gives exact per-pass timings (with it on, some passes' timings include time spent waiting for the ray tracing). 2. With **sun shadows ray-traced but projector shadows off** (Preferences > Graphics > Advanced > Shadows), to see which part costs the most. If you know whether the place you tested has a lot of alpha-masked objects (foliage, fences, hair, lace), that's helpful too.

sky_line referenced this issue

2026-10-26 02:25:11 +00:00

Prune the render configuration space (promote / remove non-default paths) #1098

sky_line self-assigned this

2026-10-26 02:58:27 +00:00

sky_line referenced this issue

2026-10-26 05:43:14 +00:00

Intel Arc (Mesa): ray-traced shadows 3.5-15 FPS in crowded regions vs 25-55 with shadow maps #1104