20649: Fix panic on race, worker shutdown vs. container startup.

[arvados.git] / lib / dispatchcloud / container / queue.go

diff --git a/lib/dispatchcloud/container/queue.go b/lib/dispatchcloud/container/queue.go
index 193c3bb20077f5ac3220a09cfe92e04628159388..77752013e8e6444431ffdb49020e9a6781b031ca 100644 (file)
--- a/lib/dispatchcloud/container/queue.go
+++ b/lib/dispatchcloud/container/queue.go
@@ -435,6 +435,13 @@ func (cq *Queue) poll() (map[string]*arvados.Container, error) {
        }
        apply(avail)
 
+       // Check for containers that we already know about but weren't
+       // returned by any of the above queries, and fetch them
+       // explicitly by UUID. If they're in a final state we can drop
+       // them, but otherwise we need to apply updates, e.g.,
+       //
+       // - Queued container priority has been reduced
+       // - Locked container has been requeued with lower priority
        missing := map[string]bool{}
        cq.mtx.Lock()
        for uuid, ent := range cq.current {