Charlie Marsh a0420114c3 Avoid storing absolute URLs for files (#944) ... ## Summary It turns out that storing an absolute URL for every file caused a significant performance regression. This PR attempts to address the regression with two changes. The first is that we now store the raw string if the URL is an absolute URL. If the URL is relative, we store the base URL alongside the raw relative string. As such, we avoid serializing and deserializing URLs until we need them (later on), except for the base URL. The second is that we now use the internal `Url` crate methods for serializing and deserializing. If you look inside `Url`, its standard serializer and deserialization actually convert it to a string, then parse the string. But the crate exposes some other methods for faster serialization and deserialization (with fewer guarantees). I think this is totally fine since the cache is entirely internal. If we _just_ change the `Url` serialization (and no other code -- so continue to store URLs for every file), then the regression goes down to about 5%: ```shell ❯ python -m scripts.bench \ --puffin-path ./target/release/main \ --puffin-path ./target/release/relative --puffin-path ./target/release/puffin \ scripts/requirements/home-assistant.in --benchmark resolve-warm Benchmark 1: ./target/release/main (resolve-warm) Time (mean ± σ): 496.3 ms ± 4.3 ms [User: 452.4 ms, System: 175.5 ms] Range (min … max): 487.3 ms … 502.4 ms 10 runs Benchmark 2: ./target/release/relative (resolve-warm) Time (mean ± σ): 284.8 ms ± 2.1 ms [User: 245.8 ms, System: 165.6 ms] Range (min … max): 280.3 ms … 288.0 ms 10 runs Benchmark 3: ./target/release/puffin (resolve-warm) Time (mean ± σ): 300.4 ms ± 3.2 ms [User: 255.5 ms, System: 178.1 ms] Range (min … max): 295.4 ms … 305.1 ms 10 runs Summary './target/release/relative (resolve-warm)' ran 1.05 ± 0.01 times faster than './target/release/puffin (resolve-warm)' 1.74 ± 0.02 times faster than './target/release/main (resolve-warm)' ``` So I considered _just_ making that change. But 5% is kind of borderline... With both of these changes, the regression is down to 1-2%: ``` Benchmark 1: ./target/release/relative (resolve-warm) Time (mean ± σ): 282.6 ms ± 7.4 ms [User: 244.6 ms, System: 181.3 ms] Range (min … max): 275.1 ms … 318.5 ms 30 runs Benchmark 2: ./target/release/puffin (resolve-warm) Time (mean ± σ): 286.8 ms ± 2.2 ms [User: 247.0 ms, System: 169.1 ms] Range (min … max): 282.3 ms … 290.7 ms 30 runs Summary './target/release/relative (resolve-warm)' ran 1.01 ± 0.03 times faster than './target/release/puffin (resolve-warm)' ``` It's consistently ~2%-ish, but at this point it's unclear if that's due to the URL change or something other change between now and then. Closes #943.		2024-01-17 09:15:21 -05:00
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src	Avoid storing absolute URLs for files (#944)	2024-01-17 09:15:21 -05:00
Cargo.toml	Split puffin-cache into Puffin-specific and generic utilities (#728)	2023-12-25 14:38:56 +00:00