Remove looking_glass

It has largely been superseded by `perf`. It is no longer
generally useful. It can always be added to BUILD_DEPS for
the rare cases it is needed, or installed locally and
pointed to by setting its path to ERL_LIBS.

BUILD.bazel

@@ -134,10 +134,7 @@ plt(
 
 PLUGINS = all_plugins(
     rabbitmq_workspace = "",
-) + select({
+)
-    "@rules_erlang//:debug_build": ["@looking_glass//:erlang_app"],
-    "//conditions:default": [],
-})
 
 rabbitmq_home(
     name = "broker-home",
@@ -286,7 +283,6 @@ moduleindex(
         "@ct_helper//:erlang_app",
         "@emqtt//:erlang_app",
         "@inet_tcp_proxy_dist//:erlang_app",
-        "@looking_glass//:erlang_app",
         "@meck//:erlang_app",
         "@proper//:erlang_app",
         "//deps/rabbitmq_ct_client_helpers:erlang_app",

MODULE.bazel

@@ -54,13 +54,6 @@ bazel_dep(
     version = "1.1.0",
 )
 
-bazel_dep(
-    name = "com_github_rabbitmq_looking_glass",
-    version = "0.2.2",
-    dev_dependency = True,
-    repo_name = "looking_glass",
-)
-
 bazel_dep(
     name = "rabbitmq_osiris",
     version = "1.8.1",

Makefile

@@ -14,11 +14,11 @@ PACKAGES_DIR ?= $(abspath PACKAGES)
 include plugins.mk
 
 # An additional list of plugins to include in a RabbitMQ release,
-# on top of the standard plugins. For example, looking_glass.
+# on top of the standard plugins.
 #
 # Note: When including NIFs in a release make sure to build
 # them on the appropriate platform for the target environment.
-# For example build looking_glass on Linux when targeting Docker.
+# For example build on Linux when targeting Docker.
 ADDITIONAL_PLUGINS ?=
 
 DEPS = rabbit_common rabbit $(PLUGINS) $(ADDITIONAL_PLUGINS)

deps/rabbit/BUILD.bazel

@@ -186,8 +186,6 @@ test_suite_beam_files(name = "test_suite_beam_files")
 # gazelle:erlang_app_dep sysmon_handler
 # gazelle:erlang_app_dep systemd
 
-# gazelle:erlang_app_dep_exclude looking_glass
-
 rabbitmq_app(
     name = "erlang_app",
     srcs = [":all_srcs"],
@@ -253,7 +251,6 @@ plt(
     plt = "//:base_plt",
     deps = [
         "//deps/rabbitmq_cli:erlang_app",  # keep
-        "@looking_glass//:erlang_app",  # keep
     ],
 )
 

deps/rabbit/Makefile

@@ -132,11 +132,11 @@ endef
 
 LOCAL_DEPS = sasl os_mon inets compiler public_key crypto ssl syntax_tools xmerl
 
-BUILD_DEPS = rabbitmq_cli looking_glass
+BUILD_DEPS = rabbitmq_cli
 DEPS = ranch rabbit_common amqp10_common rabbitmq_prelaunch ra sysmon_handler stdout_formatter recon redbug observer_cli osiris syslog systemd seshat khepri khepri_mnesia_migration cuttlefish gen_batch_server
 TEST_DEPS = rabbitmq_ct_helpers rabbitmq_ct_client_helpers meck proper amqp_client rabbitmq_amqp_client rabbitmq_amqp1_0
 
-PLT_APPS += mnesia runtime_tools looking_glass
+PLT_APPS += mnesia runtime_tools
 
 dep_syslog = git https://github.com/schlagert/syslog 4.0.0
 dep_osiris = git https://github.com/rabbitmq/osiris v1.8.1

deps/rabbit/app.bzl

@@ -162,7 +162,6 @@ def all_beam_files(name = "all_beam_files"):
             "src/rabbit_log_queue.erl",
             "src/rabbit_log_tail.erl",
             "src/rabbit_logger_exchange_h.erl",
-            "src/rabbit_looking_glass.erl",
             "src/rabbit_maintenance.erl",
             "src/rabbit_memory_monitor.erl",
             "src/rabbit_message_interceptor.erl",
@@ -422,7 +421,6 @@ def all_test_beam_files(name = "all_test_beam_files"):
             "src/rabbit_log_queue.erl",
             "src/rabbit_log_tail.erl",
             "src/rabbit_logger_exchange_h.erl",
-            "src/rabbit_looking_glass.erl",
             "src/rabbit_maintenance.erl",
             "src/rabbit_memory_monitor.erl",
             "src/rabbit_message_interceptor.erl",
@@ -701,7 +699,6 @@ def all_srcs(name = "all_srcs"):
             "src/rabbit_log_queue.erl",
             "src/rabbit_log_tail.erl",
             "src/rabbit_logger_exchange_h.erl",
-            "src/rabbit_looking_glass.erl",
             "src/rabbit_maintenance.erl",
             "src/rabbit_memory_monitor.erl",
             "src/rabbit_message_interceptor.erl",

deps/rabbit/src/rabbit.erl

@@ -229,12 +229,6 @@
                     {requires,    [core_initialized, recovery]},
                     {enables,     routing_ready}]}).
 
--rabbit_boot_step({rabbit_looking_glass,
-                   [{description, "Looking Glass tracer and profiler"},
-                    {mfa,         {rabbit_looking_glass, boot, []}},
-                    {requires,    [core_initialized, recovery]},
-                    {enables,     routing_ready}]}).
-
 -rabbit_boot_step({rabbit_observer_cli,
                    [{description, "Observer CLI configuration"},
                     {mfa,         {rabbit_observer_cli, init, []}},

deps/rabbit/src/rabbit_looking_glass.erl

@@ -1,102 +0,0 @@
-%% This Source Code Form is subject to the terms of the Mozilla Public
-%% License, v. 2.0. If a copy of the MPL was not distributed with this
-%% file, You can obtain one at https://mozilla.org/MPL/2.0/.
-%%
-%% Copyright (c) 2007-2024 Broadcom. All Rights Reserved. The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries. All rights reserved.
-%%
-
--module(rabbit_looking_glass).
-
--ignore_xref([
-    {lg, trace, 4},
-    {lg, stop, 0},
-    {lg_callgrind, profile_many, 3}
-]).
--ignore_xref([{maps, from_list, 1}]).
-
--export([boot/0]).
--export([trace/1, trace_qq/0, profile/0, profile/1]).
--export([connections/0]).
-
-boot() ->
-    case os:getenv("RABBITMQ_TRACER") of
-        false ->
-            ok;
-        On when On =:= "1" orelse On =:= "true" ->
-            rabbit_log:info("Loading Looking Glass profiler for interactive use"),
-            case application:ensure_all_started(looking_glass) of
-                {ok, _} -> ok;
-                {error, Error} ->
-                    rabbit_log:error("Failed to start Looking Glass, reason: ~tp", [Error])
-            end;
-        Value ->
-            Input = parse_value(Value),
-            rabbit_log:info(
-                "Enabling Looking Glass profiler, input value: ~tp",
-                [Input]
-            ),
-            {ok, _} = application:ensure_all_started(looking_glass),
-            lg:trace(
-                Input,
-                lg_file_tracer,
-                "traces.lz4",
-                maps:from_list([
-                    {mode, profile},
-                    {process_dump, true},
-                    {running, true},
-                    {send, true}]
-                )
-             )
-    end.
-
-trace(Input) ->
-    lg:trace(Input,
-             lg_file_tracer,
-             "traces.lz4",
-             maps:from_list([
-                 {mode, profile},
-                 {process_dump, true},
-                 {running, true},
-                 {send, true}]
-            )).
-
-trace_qq() ->
-    dbg:stop(),
-    lg:trace([ra_server,
-              ra_server_proc,
-              rabbit_fifo,
-              queue,
-              rabbit_fifo_index
-             ],
-             lg_file_tracer,
-             "traces.lz4",
-             maps:from_list([
-                 {mode, profile}
-                 % {process_dump, true},
-                 % {running, true},
-                 % {send, true}
-                            ]
-            )),
-    timer:sleep(10000),
-    _ = lg:stop(),
-    profile().
-
-profile() ->
-    profile("callgrind.out").
-
-profile(Filename) ->
-    lg_callgrind:profile_many("traces.lz4.*", Filename, #{running => true}).
-
-%%
-%% Implementation
-%%
-
-parse_value(Value) ->
-    [begin
-        [Mod, Fun] = string:tokens(C, ":"),
-        {callback, list_to_atom(Mod), list_to_atom(Fun)}
-    end || C <- string:tokens(Value, ",")].
-
-connections() ->
-    Pids = [Pid || {{conns_sup, _}, Pid} <- ets:tab2list(ranch_server)],
-    ['_', {scope, Pids}].

deps/rabbit_common/mk/rabbitmq-early-test.mk

@@ -70,28 +70,3 @@ CT_OPTS += -ct_hooks $(wordlist 2,$(words $(CT_HOOKS_PARAM_VALUE)),$(CT_HOOKS_PA
 ifeq ($(SKIP_AS_ERROR),1)
 export RABBITMQ_CT_SKIP_AS_ERROR = true
 endif
-
-# --------------------------------------------------------------------
-# Looking Glass rules.
-# --------------------------------------------------------------------
-
-ifneq ("$(RABBITMQ_TRACER)","")
-BUILD_DEPS += looking_glass
-ERL_LIBS := "$(ERL_LIBS):../looking_glass:../lz4"
-export RABBITMQ_TRACER
-endif
-
-define lg_callgrind.erl
-lg_callgrind:profile_many("traces.lz4.*", "callgrind.out", #{running => true}),
-halt().
-endef
-
-.PHONY: profile clean-profile
-
-profile:
-	$(gen_verbose) $(call erlang,$(call lg_callgrind.erl))
-
-clean:: clean-profile
-
-clean-profile:
-	$(gen_verbose) rm -f traces.lz4.* callgrind.out.*

moduleindex.yaml

@@ -366,26 +366,6 @@ khepri_mnesia_migration:
 - mnesia_to_khepri
 - mnesia_to_khepri_converter
 - mnesia_to_khepri_example_converter
-looking_glass:
-- lg
-- lg_callgrind
-- lg_file_reader
-- lg_file_tracer
-- lg_flame
-- lg_messages
-- lg_messages_seqdiag
-- lg_rabbit_hole
-- lg_raw_console_tracer
-- lg_socket_client
-- lg_socket_tracer
-- lg_term
-- lg_tracer
-- lg_tracer_pool
-- looking_glass_app
-- looking_glass_sup
-lz4:
-- lz4_nif
-- lz4f
 meck:
 - meck
 - meck_args_matcher
@@ -678,7 +658,6 @@ rabbit:
 - rabbit_log_queue
 - rabbit_log_tail
 - rabbit_logger_exchange_h
-- rabbit_looking_glass
 - rabbit_maintenance
 - rabbit_memory_monitor
 - rabbit_message_interceptor

rabbitmq-components.mk

@@ -120,7 +120,6 @@ dep_gen_batch_server = hex 0.8.8
 dep_jose = hex 1.11.10
 dep_khepri = hex 0.13.0
 dep_khepri_mnesia_migration = hex 0.4.0
-dep_looking_glass = git https://github.com/rabbitmq/looking_glass.git main
 dep_prometheus = hex 4.11.0
 dep_ra = hex 2.11.0
 dep_ranch = hex 2.1.0