I've noticed OBS idle CPU usage (when nothing is going on) becomes a constant ~0.5% if the Settings -> Video FPS value is more than 30 and not a factor of 8.
For example, setting FPS to 60 incurs this idle CPU usage. However setting it to 64 then CPU usage drops to basically 0.
I can probably guess why (memory, bits, the 8 bits in a byte, etc) but wondering if anyone had any more technical detail for it.
Also wouldn't guess it's a bug, but possibly could be.
And for those who say "Big deal it's only 0.5%". It is noticeable to my eyes when running Overwatch in high-motion high-fps and high-refresh rate scenarios.
For those who want to test it and you're running Overwatch at more than 150fps with 144hz monitor at least:
Set OW to 60fps, go into OW and move mouse around fast. Do not pay attention to FPS, just the perceived smoothness of high motion and eye tracking ability on ingame objects when the screen is moving fast.
Then go back to OBS and set to 64 and do it again. Motion is then smoother when the CPU usage here is 0.
Tell me I'm crazy.
For example, setting FPS to 60 incurs this idle CPU usage. However setting it to 64 then CPU usage drops to basically 0.
I can probably guess why (memory, bits, the 8 bits in a byte, etc) but wondering if anyone had any more technical detail for it.
Also wouldn't guess it's a bug, but possibly could be.
And for those who say "Big deal it's only 0.5%". It is noticeable to my eyes when running Overwatch in high-motion high-fps and high-refresh rate scenarios.
For those who want to test it and you're running Overwatch at more than 150fps with 144hz monitor at least:
Set OW to 60fps, go into OW and move mouse around fast. Do not pay attention to FPS, just the perceived smoothness of high motion and eye tracking ability on ingame objects when the screen is moving fast.
Then go back to OBS and set to 64 and do it again. Motion is then smoother when the CPU usage here is 0.
Tell me I'm crazy.
15:10:20.439: CPU Name: Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz
15:10:20.439: CPU Speed: 3600MHz
15:10:20.439: Physical Cores: 8, Logical Cores: 16
15:10:20.439: Physical Memory: 32650MB Total, 22095MB Free
15:10:20.439: Windows Version: 10.0 Build 17763 (release: 1809; revision: 1817; 64-bit)
15:10:20.439: Running as administrator: true
15:10:20.439: Aero is Enabled (Aero is always on for windows 8 and above)
15:10:20.439: Windows 10 Gaming Features:
15:10:20.439: Game Bar: Off
15:10:20.439: Game DVR: Off
15:10:20.439: Game DVR Background Recording: Off
15:10:20.439: Game Mode: Off
15:10:20.440: Sec. Software Status:
15:10:20.441: Windows Defender Antivirus: enabled (AV)
15:10:20.441: Windows Firewall: enabled (FW)
15:10:20.441: Windows Defender Antivirus: enabled (ASW)
15:10:20.441: Current Date/Time: 2021-03-19, 15:10:20
15:10:20.441: Browser Hardware Acceleration: false
15:10:20.441: Portable mode: false
15:10:20.756: OBS 26.1.1 (64-bit, windows)
15:10:20.756: ---------------------------------
15:10:20.786: ---------------------------------
15:10:20.786: audio settings reset:
15:10:20.786: samples per sec: 48000
15:10:20.786: speakers: 2
15:10:20.787: ---------------------------------
15:10:20.787: Initializing D3D11...
15:10:20.787: Available Video Adapters:
15:10:20.788: Adapter 0: NVIDIA GeForce RTX 2080
15:10:20.788: Dedicated VRAM: 4104126464
15:10:20.788: Shared VRAM: 4233220096
15:10:20.788: PCI ID: 10de:1e87
15:10:20.788: Driver Version: 27.21.14.5671
15:10:20.788: output 0: pos={0, 0}, size={2560, 1440}, attached=true, refresh=165, name=LEN Y27q-20
15:10:20.788: output 1: pos={2560, 0}, size={2560, 1440}, attached=true, refresh=165, name=LEN Y27q-20
15:10:20.788: Adapter 1: Intel(R) UHD Graphics 630
15:10:20.788: Dedicated VRAM: 134217728
15:10:20.788: Shared VRAM: 4233220096
15:10:20.788: PCI ID: 8086:3e98
15:10:20.789: Driver Version: 27.20.100.8681
15:10:20.790: Loading up D3D11 on adapter NVIDIA GeForce RTX 2080 (0)
15:10:20.813: D3D11 loaded successfully, feature level used: b000
15:10:20.813: DXGI increase maximum frame latency success
15:10:20.813: D3D11 GPU priority setup success
15:10:21.105: ---------------------------------
15:10:21.105: video settings reset:
15:10:21.105: base resolution: 2560x1440
15:10:21.105: output resolution: 1920x1080
15:10:21.105: downscale filter: Lanczos
15:10:21.105: fps: 64/1
15:10:21.105: format: NV12
15:10:21.105: YUV mode: 709/Partial
15:10:21.105: NV12 texture support enabled
15:10:21.106: Audio monitoring device:
15:10:21.106: name: Default
15:10:21.106: id: default
15:10:21.108: ---------------------------------
15:10:21.110: [CoreAudio encoder]: CoreAudio AAC encoder not installed on the system or couldn't be loaded
15:10:21.110: Failed to load 'en-US' text for module: 'decklink-captions.dll'
15:10:21.111: Failed to load 'en-US' text for module: 'decklink-ouput-ui.dll'
15:10:21.128: [AMF] Unable to load 'amfrt64.dll', error code 126.
15:10:21.130: [AMF] AMF Test failed due to one or more errors.
15:10:21.130: Failed to initialize module 'enc-amf.dll'
15:10:21.142: [obs-browser]: Version 2.9.1
15:10:21.142: [obs-browser]: CEF Version 75.1.16+g16a67c4+chromium-75.0.3770.100
15:10:21.144: NVENC supported
15:10:21.193: VLC found, VLC video source enabled
15:10:21.197: A DeckLink iterator could not be created. The DeckLink drivers may not be installed
15:10:21.197: No blackmagic support
15:10:21.200: ---------------------------------
15:10:21.200: Loaded Modules:
15:10:21.200: win-wasapi.dll
15:10:21.200: win-mf.dll
15:10:21.200: win-dshow.dll
15:10:21.200: win-decklink.dll
15:10:21.200: win-capture.dll
15:10:21.200: vlc-video.dll
15:10:21.200: text-freetype2.dll
15:10:21.200: rtmp-services.dll
15:10:21.200: obs-x264.dll
15:10:21.200: obs-vst.dll
15:10:21.200: obs-transitions.dll
15:10:21.200: obs-text.dll
15:10:21.200: obs-qsv11.dll
15:10:21.200: obs-outputs.dll
15:10:21.200: obs-filters.dll
15:10:21.200: obs-ffmpeg.dll
15:10:21.200: obs-browser.dll
15:10:21.200: image-source.dll
15:10:21.200: frontend-tools.dll
15:10:21.200: enc-amf.dll
15:10:21.200: decklink-ouput-ui.dll
15:10:21.200: decklink-captions.dll
15:10:21.200: coreaudio-encoder.dll
15:10:21.200: ---------------------------------
15:10:21.200: ==== Startup complete ===============================================
15:10:21.203: All scene data cleared
15:10:21.203: ------------------------------------------------
15:10:21.250: WASAPI: Device 'Speakers (Focusrite Usb Audio)' [48000 Hz] initialized
15:10:21.250: [Loaded global audio device]: 'Desktop Audio'
15:10:21.279: WASAPI: Device 'Analogue 1 + 2 (Focusrite Usb Audio)' [48000 Hz] initialized
15:10:21.279: [Loaded global audio device]: 'Mic/Aux'
15:10:21.280: Switched to scene 'Scene'
15:10:21.280: ------------------------------------------------
15:10:21.280: Loaded scenes:
15:10:21.280: - scene 'Scene':
15:10:21.280: ------------------------------------------------
15:10:57.593: ---------------------------------
15:10:57.593: video settings reset:
15:10:57.593: base resolution: 2560x1440
15:10:57.593: output resolution: 1920x1080
15:10:57.593: downscale filter: Lanczos
15:10:57.593: fps: 60/1
15:10:57.593: format: NV12
15:10:57.593: YUV mode: 709/Partial
15:10:57.593: NV12 texture support enabled
15:10:57.602: Settings changed (video)
15:10:57.602: ------------------------------------------------
15:11:45.378: ---------------------------------
15:11:45.378: video settings reset:
15:11:45.378: base resolution: 2560x1440
15:11:45.378: output resolution: 1920x1080
15:11:45.378: downscale filter: Lanczos
15:11:45.378: fps: 30/1
15:11:45.378: format: NV12
15:11:45.378: YUV mode: 709/Partial
15:11:45.378: NV12 texture support enabled
15:11:45.387: Settings changed (video)
15:11:45.387: ------------------------------------------------
15:12:14.613: ---------------------------------
15:12:14.613: video settings reset:
15:12:14.613: base resolution: 2560x1440
15:12:14.613: output resolution: 1920x1080
15:12:14.613: downscale filter: Lanczos
15:12:14.613: fps: 59/1
15:12:14.613: format: NV12
15:12:14.613: YUV mode: 709/Partial
15:12:14.613: NV12 texture support enabled
15:12:14.622: Settings changed (video)
15:12:14.622: ------------------------------------------------
15:12:38.547: ---------------------------------
15:12:38.547: video settings reset:
15:12:38.547: base resolution: 2560x1440
15:12:38.547: output resolution: 1920x1080
15:12:38.547: downscale filter: Lanczos
15:12:38.547: fps: 80/1
15:12:38.547: format: NV12
15:12:38.547: YUV mode: 709/Partial
15:12:38.547: NV12 texture support enabled
15:12:38.556: Settings changed (video)
15:12:38.556: ------------------------------------------------
15:12:59.936: ---------------------------------
15:12:59.936: video settings reset:
15:12:59.936: base resolution: 2560x1440
15:12:59.936: output resolution: 1920x1080
15:12:59.936: downscale filter: Lanczos
15:12:59.936: fps: 79/1
15:12:59.936: format: NV12
15:12:59.936: YUV mode: 709/Partial
15:12:59.936: NV12 texture support enabled
15:12:59.945: Settings changed (video)
15:12:59.945: ------------------------------------------------
15:18:14.495: ---------------------------------
15:18:14.495: video settings reset:
15:18:14.495: base resolution: 2560x1440
15:18:14.495: output resolution: 1920x1080
15:18:14.495: downscale filter: Lanczos
15:18:14.495: fps: 64/1
15:18:14.495: format: NV12
15:18:14.495: YUV mode: 709/Partial
15:18:14.495: NV12 texture support enabled
15:18:14.499: Settings changed (video)
15:18:14.499: ------------------------------------------------
15:10:20.439: CPU Speed: 3600MHz
15:10:20.439: Physical Cores: 8, Logical Cores: 16
15:10:20.439: Physical Memory: 32650MB Total, 22095MB Free
15:10:20.439: Windows Version: 10.0 Build 17763 (release: 1809; revision: 1817; 64-bit)
15:10:20.439: Running as administrator: true
15:10:20.439: Aero is Enabled (Aero is always on for windows 8 and above)
15:10:20.439: Windows 10 Gaming Features:
15:10:20.439: Game Bar: Off
15:10:20.439: Game DVR: Off
15:10:20.439: Game DVR Background Recording: Off
15:10:20.439: Game Mode: Off
15:10:20.440: Sec. Software Status:
15:10:20.441: Windows Defender Antivirus: enabled (AV)
15:10:20.441: Windows Firewall: enabled (FW)
15:10:20.441: Windows Defender Antivirus: enabled (ASW)
15:10:20.441: Current Date/Time: 2021-03-19, 15:10:20
15:10:20.441: Browser Hardware Acceleration: false
15:10:20.441: Portable mode: false
15:10:20.756: OBS 26.1.1 (64-bit, windows)
15:10:20.756: ---------------------------------
15:10:20.786: ---------------------------------
15:10:20.786: audio settings reset:
15:10:20.786: samples per sec: 48000
15:10:20.786: speakers: 2
15:10:20.787: ---------------------------------
15:10:20.787: Initializing D3D11...
15:10:20.787: Available Video Adapters:
15:10:20.788: Adapter 0: NVIDIA GeForce RTX 2080
15:10:20.788: Dedicated VRAM: 4104126464
15:10:20.788: Shared VRAM: 4233220096
15:10:20.788: PCI ID: 10de:1e87
15:10:20.788: Driver Version: 27.21.14.5671
15:10:20.788: output 0: pos={0, 0}, size={2560, 1440}, attached=true, refresh=165, name=LEN Y27q-20
15:10:20.788: output 1: pos={2560, 0}, size={2560, 1440}, attached=true, refresh=165, name=LEN Y27q-20
15:10:20.788: Adapter 1: Intel(R) UHD Graphics 630
15:10:20.788: Dedicated VRAM: 134217728
15:10:20.788: Shared VRAM: 4233220096
15:10:20.788: PCI ID: 8086:3e98
15:10:20.789: Driver Version: 27.20.100.8681
15:10:20.790: Loading up D3D11 on adapter NVIDIA GeForce RTX 2080 (0)
15:10:20.813: D3D11 loaded successfully, feature level used: b000
15:10:20.813: DXGI increase maximum frame latency success
15:10:20.813: D3D11 GPU priority setup success
15:10:21.105: ---------------------------------
15:10:21.105: video settings reset:
15:10:21.105: base resolution: 2560x1440
15:10:21.105: output resolution: 1920x1080
15:10:21.105: downscale filter: Lanczos
15:10:21.105: fps: 64/1
15:10:21.105: format: NV12
15:10:21.105: YUV mode: 709/Partial
15:10:21.105: NV12 texture support enabled
15:10:21.106: Audio monitoring device:
15:10:21.106: name: Default
15:10:21.106: id: default
15:10:21.108: ---------------------------------
15:10:21.110: [CoreAudio encoder]: CoreAudio AAC encoder not installed on the system or couldn't be loaded
15:10:21.110: Failed to load 'en-US' text for module: 'decklink-captions.dll'
15:10:21.111: Failed to load 'en-US' text for module: 'decklink-ouput-ui.dll'
15:10:21.128: [AMF] Unable to load 'amfrt64.dll', error code 126.
15:10:21.130: [AMF] AMF Test failed due to one or more errors.
15:10:21.130: Failed to initialize module 'enc-amf.dll'
15:10:21.142: [obs-browser]: Version 2.9.1
15:10:21.142: [obs-browser]: CEF Version 75.1.16+g16a67c4+chromium-75.0.3770.100
15:10:21.144: NVENC supported
15:10:21.193: VLC found, VLC video source enabled
15:10:21.197: A DeckLink iterator could not be created. The DeckLink drivers may not be installed
15:10:21.197: No blackmagic support
15:10:21.200: ---------------------------------
15:10:21.200: Loaded Modules:
15:10:21.200: win-wasapi.dll
15:10:21.200: win-mf.dll
15:10:21.200: win-dshow.dll
15:10:21.200: win-decklink.dll
15:10:21.200: win-capture.dll
15:10:21.200: vlc-video.dll
15:10:21.200: text-freetype2.dll
15:10:21.200: rtmp-services.dll
15:10:21.200: obs-x264.dll
15:10:21.200: obs-vst.dll
15:10:21.200: obs-transitions.dll
15:10:21.200: obs-text.dll
15:10:21.200: obs-qsv11.dll
15:10:21.200: obs-outputs.dll
15:10:21.200: obs-filters.dll
15:10:21.200: obs-ffmpeg.dll
15:10:21.200: obs-browser.dll
15:10:21.200: image-source.dll
15:10:21.200: frontend-tools.dll
15:10:21.200: enc-amf.dll
15:10:21.200: decklink-ouput-ui.dll
15:10:21.200: decklink-captions.dll
15:10:21.200: coreaudio-encoder.dll
15:10:21.200: ---------------------------------
15:10:21.200: ==== Startup complete ===============================================
15:10:21.203: All scene data cleared
15:10:21.203: ------------------------------------------------
15:10:21.250: WASAPI: Device 'Speakers (Focusrite Usb Audio)' [48000 Hz] initialized
15:10:21.250: [Loaded global audio device]: 'Desktop Audio'
15:10:21.279: WASAPI: Device 'Analogue 1 + 2 (Focusrite Usb Audio)' [48000 Hz] initialized
15:10:21.279: [Loaded global audio device]: 'Mic/Aux'
15:10:21.280: Switched to scene 'Scene'
15:10:21.280: ------------------------------------------------
15:10:21.280: Loaded scenes:
15:10:21.280: - scene 'Scene':
15:10:21.280: ------------------------------------------------
15:10:57.593: ---------------------------------
15:10:57.593: video settings reset:
15:10:57.593: base resolution: 2560x1440
15:10:57.593: output resolution: 1920x1080
15:10:57.593: downscale filter: Lanczos
15:10:57.593: fps: 60/1
15:10:57.593: format: NV12
15:10:57.593: YUV mode: 709/Partial
15:10:57.593: NV12 texture support enabled
15:10:57.602: Settings changed (video)
15:10:57.602: ------------------------------------------------
15:11:45.378: ---------------------------------
15:11:45.378: video settings reset:
15:11:45.378: base resolution: 2560x1440
15:11:45.378: output resolution: 1920x1080
15:11:45.378: downscale filter: Lanczos
15:11:45.378: fps: 30/1
15:11:45.378: format: NV12
15:11:45.378: YUV mode: 709/Partial
15:11:45.378: NV12 texture support enabled
15:11:45.387: Settings changed (video)
15:11:45.387: ------------------------------------------------
15:12:14.613: ---------------------------------
15:12:14.613: video settings reset:
15:12:14.613: base resolution: 2560x1440
15:12:14.613: output resolution: 1920x1080
15:12:14.613: downscale filter: Lanczos
15:12:14.613: fps: 59/1
15:12:14.613: format: NV12
15:12:14.613: YUV mode: 709/Partial
15:12:14.613: NV12 texture support enabled
15:12:14.622: Settings changed (video)
15:12:14.622: ------------------------------------------------
15:12:38.547: ---------------------------------
15:12:38.547: video settings reset:
15:12:38.547: base resolution: 2560x1440
15:12:38.547: output resolution: 1920x1080
15:12:38.547: downscale filter: Lanczos
15:12:38.547: fps: 80/1
15:12:38.547: format: NV12
15:12:38.547: YUV mode: 709/Partial
15:12:38.547: NV12 texture support enabled
15:12:38.556: Settings changed (video)
15:12:38.556: ------------------------------------------------
15:12:59.936: ---------------------------------
15:12:59.936: video settings reset:
15:12:59.936: base resolution: 2560x1440
15:12:59.936: output resolution: 1920x1080
15:12:59.936: downscale filter: Lanczos
15:12:59.936: fps: 79/1
15:12:59.936: format: NV12
15:12:59.936: YUV mode: 709/Partial
15:12:59.936: NV12 texture support enabled
15:12:59.945: Settings changed (video)
15:12:59.945: ------------------------------------------------
15:18:14.495: ---------------------------------
15:18:14.495: video settings reset:
15:18:14.495: base resolution: 2560x1440
15:18:14.495: output resolution: 1920x1080
15:18:14.495: downscale filter: Lanczos
15:18:14.495: fps: 64/1
15:18:14.495: format: NV12
15:18:14.495: YUV mode: 709/Partial
15:18:14.495: NV12 texture support enabled
15:18:14.499: Settings changed (video)
15:18:14.499: ------------------------------------------------