From 29ac62c6f8c2795b2104ca1c7f7e387c51754fd1 Mon Sep 17 00:00:00 2001
From: Raphael Taylor-Davies <1781103+tustvold@users.noreply.github.com>
Date: Tue, 10 Aug 2021 12:47:08 +0100
Subject: [PATCH] fix: reduce flakiness of lock_tracker_metrics test (#2238)

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
---
 server/src/db.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/server/src/db.rs b/server/src/db.rs
index c2d5ef8a2c..ae79f37ff9 100644
--- a/server/src/db.rs
+++ b/server/src/db.rs
@@ -3747,15 +3747,21 @@ mod tests {
         let chunks = db.catalog.chunks();
         assert_eq!(chunks.len(), 1);
 
+        let (sender, receiver) = tokio::sync::oneshot::channel();
+
         let chunk_a = Arc::clone(&chunks[0]);
         let chunk_b = Arc::clone(&chunks[0]);
 
         let chunk_b = chunk_b.write();
 
         let task = tokio::spawn(async move {
+            sender.send(()).unwrap();
             let _ = chunk_a.read();
         });
 
+        // Wait for background task to reach lock
+        let _ = receiver.await.unwrap();
+
         // Hold lock for 100 milliseconds blocking background task
         std::thread::sleep(std::time::Duration::from_millis(100));