Fix concurrent map crash in UptimePerService #132
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
fatal error: concurrent map iteration and map write
goroutine 366332 [running]:
internal/runtime/maps.fatal({0x108cc23?, 0x47bc2f?})
/usr/local/go/src/runtime/panic.go:1046 +0x18
internal/runtime/maps.(*Iter).Next(0xc000b09640?)
/usr/local/go/src/internal/runtime/maps/table.go:792 +0x86
quotient/www/api.GetUptimeStatus({0x121bb10, 0xc0004fc5a0}, 0xc000210b40)
/src/www/api/graphs.go:198 +0x91b
net/http.HandlerFunc.ServeHTTP(...)
/usr/local/go/src/net/http/server.go:2322
quotient/www/middleware.Logging.func1({0x121bb10, 0xc0004fc5a0}, 0xc000210b40)
/src/www/middleware/logging.go:25 +0x2b8
net/http.HandlerFunc.ServeHTTP(...)
/usr/local/go/src/net/http/server.go:2322
quotient/www/middleware.Cors.func1({0x121bb10, 0xc0004fc5a0}, 0xc000210b40)
/src/www/middleware/cors.go:18 +0x272
quotient/www.(*Router).Start.Authentication.func2.1({0x121bb10, 0xc0004fc5a0}, 0xc000210a00)
/src/www/middleware/authentication.go:41 +0x31e
net/http.HandlerFunc.ServeHTTP(0xc00045aa80?, {0x121bb10?, 0xc0004fc5a0?}, 0xec4500?)
/usr/local/go/src/net/http/server.go:2322 +0x29
net/http.(*ServeMux).ServeHTTP(0x12?, {0x121bb10, 0xc0004fc5a0}, 0xc000210a00)
/usr/local/go/src/net/http/server.go:2861 +0x1c7
The engine goroutine was writing to se.UptimePerService in processCollectedResults while an HTTP handler was iterating the same map in GetUptimeStatus at graphs.go:198. Go's runtime detected this and killed the process.