From e0696d324a7645f8280c1ece20556e8d352aa612 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arnaud=20Cogolu=C3=A8gnes?=
 <514737+acogoluegnes@users.noreply.github.com>
Date: Fri, 4 Jul 2025 08:18:34 +0000
Subject: [PATCH] Return stream frame header binary in dispatch chunk callback

This saves a system call by sending the frame header and the chunk
header at the same time.

References rabbitmq/osiris#192
---
 .../src/rabbit_stream_reader.erl              | 26 +++++++------------
 rabbitmq-components.mk                        |  2 +-
 2 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/deps/rabbitmq_stream/src/rabbit_stream_reader.erl b/deps/rabbitmq_stream/src/rabbit_stream_reader.erl
index 3217409b3bf..287246cb771 100644
--- a/deps/rabbitmq_stream/src/rabbit_stream_reader.erl
+++ b/deps/rabbitmq_stream/src/rabbit_stream_reader.erl
@@ -3550,12 +3550,9 @@ subscription_exists(StreamSubscriptions, SubscriptionId) ->
     lists:any(fun(Id) -> Id =:= SubscriptionId end, SubscriptionIds).
 
 send_file_callback(?VERSION_1,
-                   Transport,
                    _Log,
                    #consumer{configuration =
-                                 #consumer_configuration{socket = S,
-                                                         subscription_id =
-                                                             SubscriptionId,
+                                 #consumer_configuration{subscription_id = SubId,
                                                          counters = Counters}},
                    Counter) ->
     fun(#{chunk_id := FirstOffsetInChunk, num_entries := NumEntries},
@@ -3566,19 +3563,16 @@ send_file_callback(?VERSION_1,
              ?REQUEST:1,
              ?COMMAND_DELIVER:15,
              ?VERSION_1:16,
-             SubscriptionId:8/unsigned>>,
-       Transport:send(S, FrameBeginning),
+             SubId:8/unsigned>>,
        atomics:add(Counter, 1, Size),
        increase_messages_consumed(Counters, NumEntries),
-       set_consumer_offset(Counters, FirstOffsetInChunk)
+       set_consumer_offset(Counters, FirstOffsetInChunk),
+       FrameBeginning
     end;
 send_file_callback(?VERSION_2,
-                   Transport,
                    Log,
                    #consumer{configuration =
-                                 #consumer_configuration{socket = S,
-                                                         subscription_id =
-                                                             SubscriptionId,
+                                 #consumer_configuration{subscription_id = SubId,
                                                          counters = Counters}},
                    Counter) ->
     fun(#{chunk_id := FirstOffsetInChunk, num_entries := NumEntries},
@@ -3590,12 +3584,12 @@ send_file_callback(?VERSION_2,
              ?REQUEST:1,
              ?COMMAND_DELIVER:15,
              ?VERSION_2:16,
-             SubscriptionId:8/unsigned,
+             SubId:8/unsigned,
              CommittedChunkId:64>>,
-       Transport:send(S, FrameBeginning),
        atomics:add(Counter, 1, Size),
        increase_messages_consumed(Counters, NumEntries),
-       set_consumer_offset(Counters, FirstOffsetInChunk)
+       set_consumer_offset(Counters, FirstOffsetInChunk),
+       FrameBeginning
     end.
 
 send_chunks(DeliverVersion,
@@ -3665,9 +3659,7 @@ send_chunks(DeliverVersion,
             Retry,
             Counter) ->
     case osiris_log:send_file(Socket, Log,
-                              send_file_callback(DeliverVersion,
-                                                 Transport,
-                                                 Log,
+                              send_file_callback(DeliverVersion, Log,
                                                  Consumer,
                                                  Counter))
     of
diff --git a/rabbitmq-components.mk b/rabbitmq-components.mk
index 0b2fa759729..626e68ff68d 100644
--- a/rabbitmq-components.mk
+++ b/rabbitmq-components.mk
@@ -49,7 +49,7 @@ dep_jose = hex 1.11.10
 dep_khepri = hex 0.17.2
 dep_khepri_mnesia_migration = hex 0.8.0
 dep_meck = hex 1.0.0
-dep_osiris = git https://github.com/rabbitmq/osiris v1.9.0
+dep_osiris = git https://github.com/rabbitmq/osiris send-file-improvements
 dep_prometheus = hex 5.1.1
 dep_ra = hex 2.17.0
 dep_ranch = hex 2.2.0