Avoid calling very slow steady_clock::now#132
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josephbirkner merged 1 commit intomainfrom Dec 10, 2025
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Unfortunately, steady_clock calls in WASM translate to native JS calls, which bottlenecks simfil in the browser in extreme ways: The steady_clock calls cause a roughly 69% slowdown, maybe more, both on Chrome and Firefox. E.g. in a heavy tile render call we spend 115ms in simfil eval; 80ms of this time are spent in the emscripten steady_clock implementation!
On the Desktop, the impact is just 10%, but still worth it.
For completion (i.e. when a timeout is set), we need to consider a different implementation. For example, we could check the timeout in-between evals for individual features in the WASM workers, not for each Expr eval in simfil.
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