diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index fcbde10529..cc51a0ea44 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7051,6 +7051,7 @@ CheckPointGuts(XLogRecPtr checkPointRedo, int flags)
 	CheckPointSUBTRANS();
 	CheckPointMultiXact();
 	CheckPointPredicate();
+	sleep(3);
 	CheckPointBuffers(flags);
 
 	/* Perform all queued up fsyncs */
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index 93f07e49b7..3785ecd699 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -28,6 +28,7 @@
 #include "catalog/storage.h"
 #include "catalog/storage_xlog.h"
 #include "miscadmin.h"
+#include "postmaster/bgwriter.h" /* XXX for RequestCheckpoint() (!!!) */
 #include "storage/freespace.h"
 #include "storage/smgr.h"
 #include "utils/hsearch.h"
@@ -389,6 +390,9 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
 			XLogFlush(lsn);
 	}
 
+	/* XXX unlucky timing, a checkpoint happens to start now */
+	RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE);
+
 	/*
 	 * This will first remove any buffers from the buffer pool that should no
 	 * longer exist after truncation is complete, and then truncate the
diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c
index 5d0f3d515c..30ef9263f4 100644
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@@ -663,6 +663,8 @@ smgrtruncate(SMgrRelation reln, ForkNumber *forknum, int nforks, BlockNumber *nb
 	 */
 	DropRelationBuffers(reln, forknum, nforks, nblocks);
 
+	sleep(5);
+
 	/*
 	 * Send a shared-inval message to force other backends to close any smgr
 	 * references they may have for this rel.  This is useful because they