Only start the blockupdate thread if we're not in proxy mode

src/stratifier.c

@@ -1757,6 +1757,7 @@ int stratifier(proc_instance_t *pi)
 	create_pthread(&pth_stratum_sender, stratum_sender, ckp);
 
 	cklock_init(&workbase_lock);
+	if (!ckp->proxy)
 		create_pthread(&pth_blockupdate, blockupdate, ckp);
 
 	mutex_init(&stats_lock);