[PATCH proxmox-backup v2 1/3] server: pull: run blocking file operations on the blocking pool

[Jakob Klocker <j.klocker@proxmox.com>]

The atomic renames and the unreferenced-file cleanup are blocking
operations that ran directly on the runtime's worker threads, stalling
other tasks scheduled there for their duration.

Use the tokio counterpart for the renames and move the cleanup onto the
blocking thread pool.

Signed-off-by: Jakob Klocker <j.klocker@proxmox.com>
---
 src/server/pull.rs | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/server/pull.rs b/src/server/pull.rs
index 4eb5bcf11..fd401ac85 100644
--- a/src/server/pull.rs
+++ b/src/server/pull.rs
@@ -600,7 +600,7 @@ async fn pull_single_archive<'a>(
     } else {
         tmp_path
     };
-    if let Err(err) = std::fs::rename(&source_path, &path) {
+    if let Err(err) = tokio::fs::rename(&source_path, &path).await {
         bail!("{archive_prefix}: Atomic rename file {path:?} failed - {err}");
     }
 
@@ -890,7 +890,7 @@ async fn pull_snapshot<'a>(
         nix::unistd::fsync(tmp_manifest_file.as_raw_fd())?;
     }
 
-    if let Err(err) = std::fs::rename(&tmp_manifest_name, &manifest_name) {
+    if let Err(err) = tokio::fs::rename(&tmp_manifest_name, &manifest_name).await {
         bail!("{prefix}: Atomic rename file {manifest_name:?} failed - {err}");
     }
     if let DatastoreBackend::S3(s3_client) = backend {
@@ -910,8 +910,9 @@ async fn pull_snapshot<'a>(
 
     fetch_log(crypt_config).await?;
 
-    snapshot
-        .cleanup_unreferenced_files(&manifest)
+    let snapshot = snapshot.clone();
+    tokio::task::spawn_blocking(move || snapshot.cleanup_unreferenced_files(&manifest))
+        .await?
         .map_err(|err| format_err!("{prefix}: failed to cleanup unreferenced files - {err}"))?;
 
     Ok(Some(sync_stats))
-- 
2.47.3