client: flush the mdlog before waiting for unsafe requests

For safe replies the clients need to wait the MDS daemons to flush
the journal logs to Rados first. The worst case it will take 5 seconds.

Just trigger to flush the journal logs before waiting.

Fixes: https://tracker.ceph.com/issues/59705
Signed-off-by: Xiubo Li <xiubli@redhat.com>

diff --git a/src/client/Client.cc b/src/client/Client.cc
index a456ea2b81fe64d3c388c510d3da2fb95f73e679..e930edb047cc4ed9a6d1819efdd272b9ff12a4a3 100644 (file)
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -11940,6 +11940,9 @@ int Client::_sync_fs()
   flush_caps_sync();
   ceph_tid_t flush_tid = last_flush_tid;
 
+  // flush the mdlog before waiting for unsafe requests.
+  flush_mdlog_sync();
+
   // wait for unsafe mds requests
   wait_unsafe_requests();