LU-4604 lfsck: LFSCK async updates RPC flow control

[fs/lustre-release.git] / lustre / lfsck / lfsck_layout.c

diff --git a/lustre/lfsck/lfsck_layout.c b/lustre/lfsck/lfsck_layout.c
index 01e3151..b01122e 100644 (file)
--- a/lustre/lfsck/lfsck_layout.c
+++ b/lustre/lfsck/lfsck_layout.c
@@ -3380,11 +3380,15 @@ static int lfsck_layout_assistant(void *args)
                        rc = lfsck_layout_assistant_handle_one(env, com, llr);
                        spin_lock(&llmd->llmd_lock);
                        list_del_init(&llr->llr_list);
-                       if (bk->lb_async_windows != 0 &&
-                           llmd->llmd_prefetched >= bk->lb_async_windows)
-                               wakeup = true;
-
                        llmd->llmd_prefetched--;
+                       /* Wake up the main engine thread only when the list
+                        * is empty or half of the prefetched items have been
+                        * handled to avoid too frequent thread schedule. */
+                       if (llmd->llmd_prefetched == 0 ||
+                           (bk->lb_async_windows != 0 &&
+                            (bk->lb_async_windows >> 1) ==
+                            llmd->llmd_prefetched))
+                               wakeup = true;
                        spin_unlock(&llmd->llmd_lock);
                        if (wakeup)
                                wake_up_all(&mthread->t_ctl_waitq);
@@ -3394,9 +3398,6 @@ static int lfsck_layout_assistant(void *args)
                                GOTO(cleanup1, rc);
                }
 
-               /* Wakeup the master engine if it is waiting in checkpoint. */
-               wake_up_all(&mthread->t_ctl_waitq);
-
                l_wait_event(athread->t_ctl_waitq,
                             !lfsck_layout_req_empty(llmd) ||
                             llmd->llmd_exit ||