From 3096786454d868dd8a21bc861991b9ce6dd2bc85 Mon Sep 17 00:00:00 2001
From: Sumner Evans <sumner@beeper.com>
Date: Sat, 30 Apr 2022 01:03:53 -0600
Subject: [PATCH] backfill queue: interrupt sending to deferred channel on
 queue re-check

If a queue re-check is requested, interrupt sending the backfill request
to the deferred channel so that immediate backfills can happen ASAP.
---
 backfillqueue.go | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/backfillqueue.go b/backfillqueue.go
index 4a1c651..57ad1a6 100644
--- a/backfillqueue.go
+++ b/backfillqueue.go
@@ -40,7 +40,14 @@ func (bq *BackfillQueue) RunLoop(user *User) {
 			if backfill.BackfillType == database.BackfillImmediate || backfill.BackfillType == database.BackfillForward {
 				bq.ImmediateBackfillRequests <- backfill
 			} else {
-				bq.DeferredBackfillRequests <- backfill
+				select {
+				case <-bq.ReCheckQueue:
+					// If a queue re-check is requested, interrupt sending the
+					// backfill request to the deferred channel so that
+					// immediate backfills can happen ASAP.
+					continue
+				case bq.DeferredBackfillRequests <- backfill:
+				}
 			}
 			backfill.MarkDone()
 		} else {