Turbopack: Pass asset_suffix_path as Vc#89899
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We need to pass it by vc instead of by value, otherwise we create a new chunking context Vc for every build, which duplicates the whole build in cache (and compiles it again)
Measure Turbopack cache size (.next/cache/turbopack/) before and after rebuild cycles to detect unbounded cache growth regressions. Normal changes are limited to 10% growth; renames allow up to 50% due to dead cache entries from old routes persisting.
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Stats from current PR✅ No significant changes detected📊 All Metrics📖 Metrics GlossaryDev Server Metrics:
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📦 Bundle SizesBundle Sizes⚡ TurbopackClient Main Bundles: **437 kB** → **437 kB** ✅ -3 B81 files with content-based hashes (individual files not comparable between builds) Server Middleware
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sokra
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mischnic
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bgw
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Feb 12, 2026
| let css_url_suffix = css_url_suffix.owned().await?; | ||
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| let next_mode = mode.await?; | ||
| let asset_prefix = asset_prefix.owned().await?; |
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[Re: line +513]
should you keep it as a VC through here as well?
See this comment inline on Graphite.
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Summary
asset_suffix_pathasVc<Option<RcStr>>instead of eagerly resolving it toOption<RcStr>in the chunking context option structsWhy
Previously,
css_url_suffixwas eagerly awaited inproject.rsbefore being passed intoClientChunkingContextOptions,ServerChunkingContextOptions, andEdgeChunkingContextOptions. This caused a new chunking contextVcto be created for every build, duplicating the entire build in cache and recompiling it.By keeping it as a
Vc, the chunking context identity is stable across builds, preventing unnecessary cache duplication.How
css_url_suffixfield fromOption<RcStr>toVc<Option<RcStr>>in all three chunking context option structs.owned().await?.clone()inproject.rs(3 call sites), passing theVcdirectly.owned().await?at the point of use in the 5 context builder functionsfilesystem-cache.test.ts: normal changes limited to 10% growth, renames allow up to 50% due to dead cache entries