test(spanner): fix flaky TestMaintainer test (#3237)
* test(spanner): fix flaky TestMaintainer test
Fixes #3230
* docs: clearify comment
diff --git a/spanner/session_test.go b/spanner/session_test.go
index b868ee8..4f4fdfc 100644
--- a/spanner/session_test.go
+++ b/spanner/session_test.go
@@ -1557,7 +1557,7 @@
waitFor(t, func() error {
sp.mu.Lock()
defer sp.mu.Unlock()
- if sp.numOpened != 5 {
+ if sp.numOpened != minOpened {
return fmt.Errorf("Replenish. Expect %d open, got %d", sp.MinOpened, sp.numOpened)
}
return nil
@@ -1574,12 +1574,22 @@
t.Fatalf("cannot get session from session pool: %v", err)
}
}
- sp.mu.Lock()
- g, w := sp.numOpened, sp.MinOpened+sp.incStep
- sp.mu.Unlock()
- if g != w {
- t.Fatalf("numOpened sessions mismatch\nGot: %d\nWant: %d", g, w)
- }
+ // Wait for all sessions to be added to the pool.
+ // The pool already contained 5 sessions (MinOpened=5).
+ // The test took 20 sessions from the pool. That initiated the creation of
+ // additional sessions, and that is done in batches of 25 sessions, so the
+ // pool should contain 30 sessions (with 20 currently checked out). It
+ // could take a couple of milliseconds before all sessions have been
+ // created and added to the pool.
+ waitFor(t, func() error {
+ sp.mu.Lock()
+ defer sp.mu.Unlock()
+ g, w := sp.numOpened, sp.MinOpened+sp.incStep
+ if g != w {
+ return fmt.Errorf("numOpened sessions mismatch\nGot: %d\nWant: %d", g, w)
+ }
+ return nil
+ })
// Return 14 sessions to the pool. There are still 6 sessions checked out.
for _, sh := range shs[:14] {
