From 050dad59ead0ee29779f0846891215fb63664d4e Mon Sep 17 00:00:00 2001 From: tokikuch Date: Wed, 27 Sep 2023 00:00:27 -0700 Subject: [PATCH] core/bloombits: fix deadlock when matcher session hits an error (#1895) When MatcherSession encounters an error, it attempts to close the session. Closing waits for all goroutines to finish, including the 'distributor'. However, the distributor will not exit until all requests have returned. This patch fixes the issue by delivering the (empty) result to the distributor before calling Close(). --- core/bloombits/matcher.go | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/core/bloombits/matcher.go b/core/bloombits/matcher.go index 2bb06349a3..68be2f4cff 100644 --- a/core/bloombits/matcher.go +++ b/core/bloombits/matcher.go @@ -633,13 +633,16 @@ func (s *MatcherSession) Multiplex(batch int, wait time.Duration, mux chan chan request <- &Retrieval{Bit: bit, Sections: sections, Context: s.ctx} result := <-request + + // Deliver a result before s.Close() to avoid a deadlock + s.deliverSections(result.Bit, result.Sections, result.Bitsets) + if result.Error != nil { s.errLock.Lock() s.err = result.Error s.errLock.Unlock() s.Close() } - s.deliverSections(result.Bit, result.Sections, result.Bitsets) } } }