[pbs-devel] [PATCH proxmox-backup] sync job: pull: avoid blocking future during thread pool completion

[Christian Ebner]

Chunk insertion during a pull sync job is performed via a thread pool
to increase performance. The caller waits for all threads to be
completed at the end, relying on the respective associated threads to
return from `std::thread::JoinHandle::join`.

Insertion into the chunk store can however take time, especially
for chunks being uploaded to the object store for datastores with
S3 backend.

To avoid blocking the async runtime, spawn a dedicated task to await
the thread pool completion.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
Encountered while looking for possible causes of proxy hangs as reported
in https://forum.proxmox.com/threads/171422/post-807098

 src/server/pull.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/server/pull.rs b/src/server/pull.rs
index 08e6e6b64..53f1a570d 100644
--- a/src/server/pull.rs
+++ b/src/server/pull.rs
@@ -232,7 +232,7 @@ async fn pull_index_chunks<I: IndexFile>(
 
     drop(verify_and_write_channel);
 
-    verify_pool.complete()?;
+    let _ = tokio::task::spawn_blocking(|| verify_pool.complete()).await?;
 
     let elapsed = start_time.elapsed()?;
 
-- 
2.47.3