From 12d7479144c36bea03f7d61f8474e31603eabd84 Mon Sep 17 00:00:00 2001
From: Guy Benoish <guy.benoish@redislabs.com>
Date: Mon, 30 Mar 2020 10:52:59 +0300
Subject: [PATCH] streamReplyWithRange: Redundant XSETIDs to replica

propagate_last_id is declared outside of the loop but used
only from within the loop. Once it's '1' it will never go
back to '0' and will replicate XSETID even for IDs that
don't actually change the last_id.
While not a serious bug (XSETID always used group->last_id
so there's no risk), it does causes redundant traffic
between master and its replicas
---
 src/t_stream.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/t_stream.c b/src/t_stream.c
index 557d1d642..00d1cbf1c 100644
--- a/src/t_stream.c
+++ b/src/t_stream.c
@@ -935,7 +935,6 @@ size_t streamReplyWithRange(client *c, stream *s, streamID *start, streamID *end
     streamIterator si;
     int64_t numfields;
     streamID id;
-    int propagate_last_id = 0;
 
     /* If the client is asking for some history, we serve it using a
      * different function, so that we return entries *solely* from its
@@ -951,6 +950,8 @@ size_t streamReplyWithRange(client *c, stream *s, streamID *start, streamID *end
         arraylen_ptr = addReplyDeferredLen(c);
     streamIteratorStart(&si,s,start,end,rev);
     while(streamIteratorGetID(&si,&id,&numfields)) {
+        int propagate_last_id = 0;
+
         /* Update the group last_id if needed. */
         if (group && streamCompareID(&id,&group->last_id) > 0) {
             group->last_id = id;