From 94106cf964228559d5946ed6a0dadb532318aaa7 Mon Sep 17 00:00:00 2001
From: Aleksey Sabilin <aleksey@sabilin.com>
Date: Wed, 15 Jul 2026 17:28:39 +0300
Subject: [PATCH] =?UTF-8?q?fix(mnesia):=20=D0=BF=D0=BE=D0=B4=D0=BD=D1=8F?=
 =?UTF-8?q?=D1=82=D1=8C=20dump=5Flog=5Fwrite=5Fthreshold;=20Traefik=20base?=
 =?UTF-8?q?=20v3.3.6.=20Refs=20EventHub/EventHubBack#34=20Refs=20EventHub/?=
 =?UTF-8?q?EventHubDevOps#3=20[skip=20ci]?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 docker/traefik/Dockerfile  |  2 +-
 src/eventhub_app.erl       |  1 +
 src/infra/infra_mnesia.erl | 30 ++++++++++++++++++++++++++++++
 test/tsung/README.md       |  2 ++
 4 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/docker/traefik/Dockerfile b/docker/traefik/Dockerfile
index 13abd54..186d08a 100644
--- a/docker/traefik/Dockerfile
+++ b/docker/traefik/Dockerfile
@@ -1,4 +1,4 @@
-FROM traefik:v3.2.0
+FROM traefik:v3.3.6
 
 ARG CORAZA_VERSION=v0.3.0
 ARG CORAZA_MODULE=github.com/jcchavezs/coraza-http-wasm-traefik
diff --git a/src/eventhub_app.erl b/src/eventhub_app.erl
index 3ac444b..0c0a51a 100644
--- a/src/eventhub_app.erl
+++ b/src/eventhub_app.erl
@@ -47,6 +47,7 @@ start_application() ->
           application:set_env(eventhub, extra_db_nodes, Nodes)
       end,
       application:ensure_all_started(mnesia),
+      ok = infra_mnesia:configure_dump_log(),
       ok = infra_mnesia:init_tables(),
       ok = infra_mnesia:wait_for_tables(),
       ok = migration_engine:ensure_applied(),
diff --git a/src/infra/infra_mnesia.erl b/src/infra/infra_mnesia.erl
index 94c2cbf..55530cc 100644
--- a/src/infra/infra_mnesia.erl
+++ b/src/infra/infra_mnesia.erl
@@ -8,6 +8,7 @@
 
 -export([start_link/0, init_tables/0, wait_for_tables/0, wait_for_table/1]).
 -export([add_cluster_nodes/1]).
+-export([configure_dump_log/0]).
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
   terminate/2, code_change/3]).
 
@@ -44,6 +45,35 @@ wait_for_tables() ->
 add_cluster_nodes(Nodes) ->
   gen_server:call(?MODULE, {add_nodes, Nodes}).
 
+%% @doc Soften dump_log overload under write-heavy load (IFT stress).
+%% OTP warns {dump_log, write_threshold|time_threshold} when a new dump
+%% is requested while the previous dump still runs.
+%% Override: MNESIA_DUMP_LOG_WRITE_THRESHOLD (default 50000; OTP default ~1000).
+-spec configure_dump_log() -> ok.
+configure_dump_log() ->
+  Threshold = env_int("MNESIA_DUMP_LOG_WRITE_THRESHOLD", 50000),
+  case mnesia:change_config(dump_log_write_threshold, Threshold) of
+    {ok, Old} ->
+      io:format("Mnesia dump_log_write_threshold: ~p -> ~p~n", [Old, Threshold]),
+      ok;
+    Other ->
+      io:format("Mnesia dump_log_write_threshold change failed: ~p~n", [Other]),
+      ok
+  end.
+
+env_int(Name, Default) ->
+  case os:getenv(Name) of
+    false -> Default;
+    "" -> Default;
+    Val ->
+      try list_to_integer(Val) of
+        N when N > 0 -> N;
+        _ -> Default
+      catch
+        error:badarg -> Default
+      end
+  end.
+
 %% ===================================================================
 %% gen_server callbacks
 %% ===================================================================
diff --git a/test/tsung/README.md b/test/tsung/README.md
index 42b2c0f..c062110 100644
--- a/test/tsung/README.md
+++ b/test/tsung/README.md
@@ -62,6 +62,8 @@ IFT = Docker Swarm **внутри WSL2 на Windows**. Aggressive open-loop бе
 
 **Controlled hold ×3** (`20260715-1411/`, `EVENTHUB_REPLICAS=3`): connect по фазам 0.2→0.035 GREEN (0.05 mean≈40 ms); overall BOUNDARY_HIT из‑за **3772× HTTP 429** — узкое место сместилось на Traefik `api-ratelimit` (per source IP, было 5000/1m≈83 rps). После поднятия IFT-лимитов до 2000/1s (EventHubBack#32) перепроверить hold ×3.
 
+Под hold также: `Mnesia is overloaded: {dump_log, write_threshold|time_threshold}`. Краткосрочно: `MNESIA_DUMP_LOG_WRITE_THRESHOLD` (IFT default 50000, EventHubBack#34). Долгосрочно: меньше sync-транзакций / hot-path вне Mnesia.
+
 Restore fallback: оркестратор → WSL SSH, при fail Windows `restore-ift.ps1`.
 
 Если после stress SSH «висит на banner» — **reboot IFT**, затем: