perf(native): avoid zeroing large shmem modules array - #1966
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When creating native backend shmem, zero the crash context only up to modules[]. This initializes the header, configuration, paths, platform state, and module count that must start from zero before a crash. Leave modules[] uninitialized during startup. It is the multi-megabyte tail of the shmem crash context, and crash handling treats it as valid only up to module_count before filling it. Add a unit test that verifies the initialization boundary: the byte before modules[] is zeroed, while modules[] itself keeps its previous contents. See: #1852
Codecov Report❌ Patch coverage is Additional details and impacted files@@ Coverage Diff @@
## master #1966 +/- ##
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+ Coverage 76.15% 76.18% +0.02%
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Files 94 94
Lines 22216 22222 +6
Branches 3941 3942 +1
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+ Hits 16919 16930 +11
+ Misses 4411 4407 -4
+ Partials 886 885 -1 🚀 New features to boost your workflow:
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limbonaut
approved these changes
Aug 10, 2026
JoshuaMoelans
approved these changes
Aug 10, 2026
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Quite a bit better 
The rest will be caught up in |
1 task
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When creating shared memory for the native backend and daemon, zero the crash context only up to
module_count. Leaving the trailing ~8 MiBmodules[]array uninitialized is safe, because the array access is guarded bymodule_count.This shaves off ~40% of the current native backend startup time on Linux:
Before
After
Partial fix to: