LSW 0.2.0

Highlights

• Faster, and no longer slowing down. Shared textures were never freed until the application closed, and the driver shipped with debug consistency checks that grew with every one, so applications like Lightroom slowed with use: photo switches grew from about 350 ms to over 600 ms. They now stay flat. Released Direct3D 12 textures also leave VRAM instead of staying until the application exits.
• Guest RAM on huge pages. QEMU never gave the guest huge pages; it now does, which cuts CPU time in memory-heavy applications by about 10%.
• Lightroom's Lens Blur keeps the GPU. Upload heaps past 1 GiB removed the Direct3D 12 device, and Lightroom turned hardware acceleration off.
• Real driver versions. Applications that read the GPU driver's version (Lightroom showed 0.0.0.0 and called the GPU incapable) see the current Windows driver version for your GPU, looked up in the Microsoft Update Catalog.
• Refresh rate. Windows runs at the monitor's refresh rate, or any rate the monitors support, changed while it runs, and the window mirror keeps the display in phase without changing its rate.
• USB devices can be passed to the guest. A returned device leaves the guest at once without stalling it, and can be passed again once it has reset.
• Host shutdown and reboot power the guest off at once rather than waiting on a graceful Windows shutdown.
• Desktop latency: windows reach the compositor through lent pages copied by the GPU; input-to-screen with a full-screen Direct3D 9 cursor went from 57.5 ms median to about 45.
• Open host files in Windows from a file manager or the command line; the app list is built from the Start menu; shared folders mount after a failed swap.
• The system disk submits from QEMU's threads, which removes a stall of up to 88 ms every few seconds on btrfs.

Known limits

• Tested on an AMD RX 9070 XT host. Intel Arc and NVIDIA hosts were not tested for this release.
• QueryVideoMemoryInfo reports 0 MiB used in the guest, so applications that size their caches by it may keep growing them.