Keep the macOS viewer out of App Nap while it runs - #902
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Nothing opted out, so a covered viewer could be napped: timers coalesced and priority lowered, for a process whose loop is driven from outside a frame at a time and which answers a socket beside it. A failing test's inline send could wait on it, and the window come forward late. The runtime takes out a userInitiatedAllowingIdleSystemSleep activity when it opens and ends it at shutdown. Idle sleep is still allowed, and since the loop only redraws on a change, staying awake costs one event pump a frame.
This was referenced Sep 23, 2026
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This was referenced Sep 24, 2026
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Fixes the macOS App Nap item in
todo.md.Nothing opted out of App Nap, so a covered viewer could be napped: timers coalesced and priority lowered. This process's loop is driven from outside, one frame at a time, with a socket listener beside it. So a failing test's inline send could wait on it, and its window could come forward late.
Runtime.opennow takes out auserInitiatedAllowingIdleSystemSleepactivity, andshutdownends it. Idle sleep is still allowed. Since #898 the loop only redraws on a change, so staying out of App Nap costs one event pump per frame. It also covers a hidden viewer that owns the queue, which still has to answer every send promptly.Not verified: there's no Mac here, so CI compiling the Swift and running the macOS tests is the only check. The todo item's steps would confirm it: cover the viewer for a minute, check Activity Monitor no longer shows it napping, then time how long a failing inline test takes to bring it forward.
Binaries rebuilt by
build-native(#900, fast-forwarded into this branch).Merge #901 first. Both replace the macOS library, and #901 also moves the ABI to 9. After it merges, this branch needs
mainmerged in and its binaries rebuilt, or it would put a version 8 library back.