Stopping the game with pause, the processor continues to be loaded!

Is there an existing issue for this?

• This is a bug in RetroArch frontend
• I have searched the existing issues

Description

When you press Pause, the game stops but only visually!
The processor continues to remain loaded.
For example:
Before pressing Pause during the game: CPU 55%
After pressing Pause during the game : CPU 55%

Pause worked great in older versions of Retroarch
For example:
Retroarch v1.9.13, v1.9.14....v1.10.3 -> Pause = CPU 0%

My sys: Windows XP Pro SP3
RetroArch: https://buildbot.libretro.com/stable/1.21.0/windows-msvc2010/x86/RetroArch.7z

Expected behavior

I expected the pause to work at least as well as in older versions v1.9.13...v1.10.3

Steps to reproduce the bug

1. Start game
2. Pause game

Version/Commit

1.21.0 -> https://buildbot.libretro.com/stable/1.21.0/windows-msvc2010/x86/RetroArch.7z

Bisect Results

No response

Present in the nightly version

Yes, this is reproduced in the nightly build

Platform & operating system

Windows XP Pro SP3

Affected Cores

No response

Environment information

No response

Relevant log output

[INFO] === Build =======================================
[INFO] CPU Model Name: Intel(R) Pentium(R) M processor 2.00GHz
[INFO] Capabilities: MMX MMXEXT SSE SSE2 
[INFO] Version: 1.21.0
[INFO] Built: Apr 29 2025
[INFO] =================================================
[INFO] [Input]: Found input driver: "dinput".
[INFO] [Core]: Loading dynamic libretro core from: "C:\Z\RETROA~1\x\genesis_plus_gx_libretro.dll"
[INFO] [Overrides]: Redirecting save file to "C:\Z\RETROA~1\x\saves\PENGO.srm".
[INFO] [Overrides]: Redirecting save state to "C:\Z\RETROA~1\x\states\PENGO.state".
[INFO] [Environ]: GET_CORE_OPTIONS_VERSION.
[INFO] [Environ]: GET_LANGUAGE: "0".
[INFO] [Environ]: RETRO_ENVIRONMENT_SET_CORE_OPTIONS_V2_INTL.
[INFO] [Environ]: SET_CONTROLLER_INFO.
[INFO] [Environ]: SET_INPUT_DESCRIPTORS:
[INFO] [Environ]: RETRO_ENVIRONMENT_SET_CONTENT_INFO_OVERRIDE.
[INFO] [Content Override]: File Extension: 'mdx' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: ' md' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'bin' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'smd' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'gen' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'bms' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'sms' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: ' gg' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: ' sg' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: '68k' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Content Override]: File Extension: 'sgd' - need_fullpath: FALSE, persistent_data: FALSE
[INFO] [Environ]: GET_VFS_INTERFACE. Core requested version >= V1, providing V3.
[INFO] [Environ]: PERFORMANCE_LEVEL: 1.
[INFO] [Environ]: GET_LOG_INTERFACE.
[INFO] [Environ]: PERFORMANCE_LEVEL: 7.
[INFO] [Environ]: SET_SERIALIZATION_QUIRKS.
[INFO] [Environ]: SET_DISK_CONTROL_INTERFACE.
[INFO] [Content]: Loading content file: "C:\Z\RETROA~1\x\PENGO.BIN".
[INFO] [Environ]: RETRO_ENVIRONMENT_GET_GAME_INFO_EXT.
[INFO] [Environ]: SET_PIXEL_FORMAT: RGB565.
[libretro INFO] Frontend supports RGB565 - will use that instead of XRGB1555.
[INFO] [Environ]: SYSTEM_DIRECTORY: "C:\Z\RETROA~1\x\system".
[INFO] [Environ]: SAVE_DIRECTORY: "C:\Z\RETROA~1\x\saves".
[libretro INFO] Game Genie ROM should be located at: C:\Z\RETROA~1\x\system\ggenie.bin
[libretro INFO] Action Replay (Pro) ROM should be located at: C:\Z\RETROA~1\x\system\areplay.bin
[libretro INFO] Sonic & Knuckles (2 MB) ROM should be located at: C:\Z\RETROA~1\x\system\sk.bin
[libretro INFO] Sonic & Knuckles UPMEM (256 KB) ROM should be located at: C:\Z\RETROA~1\x\system\sk2chip.bin
[libretro INFO] Mega Drive TMSS BOOTROM should be located at: C:\Z\RETROA~1\x\system\bios_MD.bin
[libretro INFO] Game Gear TMSS BOOTROM should be located at: C:\Z\RETROA~1\x\system\bios.gg
[libretro INFO] Master System (PAL) BOOTROM should be located at: C:\Z\RETROA~1\x\system\bios_E.sms
[libretro INFO] Master System (NTSC-U) BOOTROM should be located at: C:\Z\RETROA~1\x\system\bios_U.sms
[libretro INFO] Master System (NTSC-J) BOOTROM should be located at: C:\Z\RETROA~1\x\system\bios_J.sms
[libretro INFO] Mega CD (PAL) BIOS should be located at: C:\Z\RETROA~1\x\system\bios_CD_E.bin
[libretro INFO] Sega CD (NTSC-U) BIOS should be located at: C:\Z\RETROA~1\x\system\bios_CD_U.bin
[libretro INFO] Mega CD (NTSC-J) BIOS should be located at: C:\Z\RETROA~1\x\system\bios_CD_J.bin
[libretro INFO] Mega CD (PAL) BRAM is located at: C:\Z\RETROA~1\x\saves\scd_E.brm
[libretro INFO] Sega CD (NTSC-U) BRAM is located at: C:\Z\RETROA~1\x\saves\scd_U.brm
[libretro INFO] Mega CD (NTSC-J) BRAM is located at: C:\Z\RETROA~1\x\saves\scd_J.brm
[libretro INFO] Sega/Mega CD RAM CART is located at: C:\Z\RETROA~1\x\saves\cart.brm
[INFO] [Environ]: SET_AUDIO_BUFFER_STATUS_CALLBACK.
[INFO] [SRAM]: Skipping SRAM load.
[INFO] [State]: Found auto save state in "C:\Z\RETROA~1\x\states\PENGO.state.auto".
[INFO] [State]: Auto-loading save state from "C:\Z\RETROA~1\x\states\PENGO.state.auto" succeeded.
[INFO] [Core]: Version of libretro API: 1, Compiled against API: 1
[INFO] [Core]: Geometry: 256x192, Aspect: 1.524, FPS: 59.92, Sample rate: 44100.00 Hz.
[INFO] Using 1 threads for softfilter.
[INFO] [Video]: Set video size to: 586x384.
[INFO] [XInput]: Found XInput v1.3.
[INFO] [Joypad]: Found joypad driver: "dinput".
[INFO] [Video]: Found display server: "win32".
[INFO] [Audio]: Set audio input rate to: 44156.86 Hz.
[INFO] [DirectSound]: Setting buffer size of 11264 bytes
[INFO] [DirectSound]: Latency = 63 ms
[INFO] [Audio]: Started synchronous audio driver.
[INFO] [Display]: Found display driver: "d3d8".
[INFO] [Playlist]: Loading history file: "C:\Z\RETROA~1\x\content_history.lpl".
[INFO] [Playlist]: Loading history file: "C:\Z\RETROA~1\x\content_music_history.lpl".
[INFO] [Playlist]: Loading history file: "C:\Z\RETROA~1\x\content_image_history.lpl".
[INFO] [Playlist]: Loading favorites file: "C:\Z\RETROA~1\x\content_favorites.lpl".
[INFO] [Playlist]: Written to playlist file: "C:\Z\RETROA~1\x\content_history.lpl".
[INFO] [Environ]: RETRO_ENVIRONMENT_SET_MINIMUM_AUDIO_LATENCY.
[INFO] [State]: Loading state "C:\Z\RETROA~1\x\states\PENGO.state.auto", 1036312 bytes.
[INFO] [State]: Core does not support save states.
[INFO] [Environ]: SET_GEOMETRY: 320x224, Aspect: 1.306.
[INFO] [Config]: Saved new config to "C:\Z\RETROA~1\x\retro.cfg".
[INFO] [Core]: Content ran for a total of: 00 hours, 00 minutes, 37 seconds.
[INFO] [Core]: Unloading game..
[INFO] [Core]: Unloading core..
[INFO] [Core]: Unloading core symbols..
[INFO] [Core]: Saved core options file to "C:\Z\RETROA~1\x\config\Genesis Plus GX\Genesis Plus GX.opt".
[INFO] [Playlist]: Written to playlist file: "C:\Z\RETROA~1\x\content_music_history.lpl".
[INFO] [Playlist]: Written to playlist file: "C:\Z\RETROA~1\x\content_image_history.lpl".

Start by reproducing the pause behavior with the specified RetroArch 1.21.0 Windows XP build and compare CPU usage against versions 1.9.13–1.10.3. Use the pause action and the provided log as the initial reference; the issue is done when pausing stops the processor load as expected and the behavior is verified on the nightly build.