diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 8079226..a622a18 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -94,7 +94,7 @@ static Buffer ReadBuffer_common(SMgrRelation reln, char relpersistence,
 static bool PinBuffer(volatile BufferDesc *buf, BufferAccessStrategy strategy);
 static void PinBuffer_Locked(volatile BufferDesc *buf);
 static void UnpinBuffer(volatile BufferDesc *buf, bool fixOwner);
-static void BufferSync(int flags);
+static void BufferSync(int flags, double progress_upto);
 static int	SyncOneBuffer(int buf_id, bool skip_recently_used);
 static void WaitIO(volatile BufferDesc *buf);
 static bool StartBufferIO(volatile BufferDesc *buf, bool forInput);
@@ -1207,7 +1207,7 @@ UnpinBuffer(volatile BufferDesc *buf, bool fixOwner)
  * remaining flags currently have no effect here.
  */
 static void
-BufferSync(int flags)
+BufferSync(int flags, double progress_upto)
 {
 	int			buf_id;
 	int			num_to_scan;
@@ -1319,7 +1319,7 @@ BufferSync(int flags)
 				/*
 				 * Sleep to throttle our I/O rate.
 				 */
-				CheckpointWriteDelay(flags, (double) num_written / num_to_write);
+				CheckpointWriteDelay(flags, progress_upto * (double) num_written / num_to_write);
 			}
 		}
 
@@ -1825,10 +1825,10 @@ CheckPointBuffers(int flags)
 {
 	TRACE_POSTGRESQL_BUFFER_CHECKPOINT_START(flags);
 	CheckpointStats.ckpt_write_t = GetCurrentTimestamp();
-	BufferSync(flags);
+	BufferSync(flags, 0.9);
 	CheckpointStats.ckpt_sync_t = GetCurrentTimestamp();
 	TRACE_POSTGRESQL_BUFFER_CHECKPOINT_SYNC_START();
-	smgrsync();
+	smgrsync(flags, 0.9);
 	CheckpointStats.ckpt_sync_end_t = GetCurrentTimestamp();
 	TRACE_POSTGRESQL_BUFFER_CHECKPOINT_DONE();
 }
diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c
index e629181..7ceec9c 100644
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@@ -235,7 +235,7 @@ SetForwardFsyncRequests(void)
 	/* Perform any pending fsyncs we may have queued up, then drop table */
 	if (pendingOpsTable)
 	{
-		mdsync();
+		mdsync(CHECKPOINT_IMMEDIATE, 0.0);
 		hash_destroy(pendingOpsTable);
 	}
 	pendingOpsTable = NULL;
@@ -974,7 +974,7 @@ mdimmedsync(SMgrRelation reln, ForkNumber forknum)
  *	mdsync() -- Sync previous writes to stable storage.
  */
 void
-mdsync(void)
+mdsync(int ckpt_flags, double progress_at_begin)
 {
 	static bool mdsync_in_progress = false;
 
@@ -990,6 +990,7 @@ mdsync(void)
 	uint64		elapsed;
 	uint64		longest = 0;
 	uint64		total_elapsed = 0;
+	int			ntoprocess;
 
 	/*
 	 * This is only called during checkpoints, and checkpoints should only
@@ -1052,6 +1053,7 @@ mdsync(void)
 	/* Now scan the hashtable for fsync requests to process */
 	absorb_counter = FSYNCS_PER_ABSORB;
 	hash_seq_init(&hstat, pendingOpsTable);
+	ntoprocess = hash_get_num_entries(pendingOpsTable);
 	while ((entry = (PendingOperationEntry *) hash_seq_search(&hstat)) != NULL)
 	{
 		ForkNumber	forknum;
@@ -1171,6 +1173,11 @@ mdsync(void)
 								 FilePathName(seg->mdfd_vfd),
 								 (double) elapsed / 1000);
 
+						/*
+						 * Sleep to throttle our I/O rate.
+						 */
+						CheckpointWriteDelay(ckpt_flags, progress_at_begin + (1.0 - progress_at_begin) * (double) processed / ntoprocess);
+
 						break;	/* out of retry loop */
 					}
 
diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c
index f7f1437..ec24007 100644
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@@ -58,7 +58,7 @@ typedef struct f_smgr
 											  BlockNumber nblocks);
 	void		(*smgr_immedsync) (SMgrRelation reln, ForkNumber forknum);
 	void		(*smgr_pre_ckpt) (void);		/* may be NULL */
-	void		(*smgr_sync) (void);	/* may be NULL */
+	void		(*smgr_sync) (int ckpt_flags, double progress_at_begin);	/* may be NULL */
 	void		(*smgr_post_ckpt) (void);		/* may be NULL */
 } f_smgr;
 
@@ -708,14 +708,18 @@ smgrpreckpt(void)
  *	smgrsync() -- Sync files to disk during checkpoint.
  */
 void
-smgrsync(void)
+smgrsync(int ckpt_flags, double progress_at_begin)
 {
 	int			i;
 
 	for (i = 0; i < NSmgr; i++)
 	{
+		/*
+		 * XXX: If we ever have more than one smgr, the remaining progress
+		 * should somehow be divided among all smgrs.
+		 */
 		if (smgrsw[i].smgr_sync)
-			(*(smgrsw[i].smgr_sync)) ();
+			(*(smgrsw[i].smgr_sync)) (ckpt_flags, progress_at_begin);
 	}
 }
 
diff --git a/src/include/storage/smgr.h b/src/include/storage/smgr.h
index 98b6f13..e8efcbe 100644
--- a/src/include/storage/smgr.h
+++ b/src/include/storage/smgr.h
@@ -100,7 +100,7 @@ extern void smgrtruncate(SMgrRelation reln, ForkNumber forknum,
 			 BlockNumber nblocks);
 extern void smgrimmedsync(SMgrRelation reln, ForkNumber forknum);
 extern void smgrpreckpt(void);
-extern void smgrsync(void);
+extern void smgrsync(int ckpt_flags, double progress_at_begin);
 extern void smgrpostckpt(void);
 extern void AtEOXact_SMgr(void);
 
@@ -126,7 +126,7 @@ extern void mdtruncate(SMgrRelation reln, ForkNumber forknum,
 		   BlockNumber nblocks);
 extern void mdimmedsync(SMgrRelation reln, ForkNumber forknum);
 extern void mdpreckpt(void);
-extern void mdsync(void);
+extern void mdsync(int ckpt_flags, double progress_at_begin);
 extern void mdpostckpt(void);
 
 extern void SetForwardFsyncRequests(void);