diff --git a/lib_log.c b/lib_log.c
index d8855092..2236a69e 100644
--- a/lib_log.c
+++ b/lib_log.c
@@ -152,6 +152,7 @@ void log_flush(struct log_status *logst)
 	}
 	mref->ref_len = logst->offset;
 	logst->log_pos += logst->offset;
+	memcpy(&logst->log_pos_stamp, &logst->tmp_pos_stamp, sizeof(logst->log_pos_stamp));
 
 	cb_info = logst->private;
 	logst->private = NULL;
@@ -272,6 +273,9 @@ void *log_reserve(struct log_status *logst, struct log_header *lh)
 	DATA_PUT(data, offset, lh->l_code);
 	DATA_PUT(data, offset, lh->l_extra);
 
+	// remember the last timestamp
+	memcpy(&logst->tmp_pos_stamp, &lh->l_stamp, sizeof(logst->tmp_pos_stamp));
+
 	logst->payload_offset = offset;
 	logst->payload_len = lh->l_len;
 
diff --git a/lib_log.h b/lib_log.h
index a62bf639..47326172 100644
--- a/lib_log.h
+++ b/lib_log.h
@@ -98,7 +98,9 @@ struct log_status {
 	atomic_t mref_flying;
 	int count;
 	loff_t log_pos;
+	struct timespec log_pos_stamp;
 	// internal
+	struct timespec tmp_pos_stamp;
 	struct mars_input *input;
 	struct mars_brick *brick;
 	struct mars_info info;