Fix perfromance when there's lots of error #2283
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DiagnosticsCollection#Add() used InsertSort, this causes a ton of memcopys on every error. This is O(n) for every error. Instead I moved the sort to lazily happen just before each GetDiagnostics call this is not only O(nlogn), but gets happen way less often than Inserts
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This looks fine, but you should run |
sheetalkamat
reviewed
Dec 8, 2025
internal/ast/diagnostic.go
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| c.fileDiagnostics = make(map[string][]*Diagnostic) | ||
| } | ||
| c.fileDiagnostics[fileName] = core.InsertSorted(c.fileDiagnostics[fileName], diagnostic, CompareDiagnostics) | ||
| if c.fileDiagnosticsSorted == nil { |
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Do we really need sorting here as diagnostics are anyways sorted and deduplicated at end points?
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It's sorted so lookup can find diags later; it's a weird system but yeah
jakebailey
reviewed
Dec 8, 2025
jakebailey
approved these changes
Dec 9, 2025
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This turns out to be unsafe; it causes a data race when concurrently accessing processor diagnostics. We don't see the problem in main, though, only on a WIP branch I have for bringing back #2197. |
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And, since it sorts the list on the fly, if something previously grabbed a list of diags (say, the global diags), and then they changed later, the list would potentially be concurrently modified. |
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DiagnosticsCollection#Add() uses InsertSort, this causes a ton of memcopys on every error. This is O(n) for every error.
Instead I moved the sort to lazily happen just before each GetDiagnostics call this is O(nlogn), but gets happen way less often than Inserts.
This happens on codebases with lots of usages of react-hook-form due to #988 . While this isn't a fix for that it allows builds to fail instead of hanging for hours