From 16b9eaafae08c14fa92ff6521b716de91489f60d Mon Sep 17 00:00:00 2001
From: Kirill Pleshivtsev <drbasic@yandex-team.ru>
Date: Mon, 11 Mar 2024 18:03:53 +0700
Subject: [PATCH 1/3] Write all crit events to cerr

---
 cloud/storage/core/libs/diagnostics/critical_events.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cloud/storage/core/libs/diagnostics/critical_events.cpp b/cloud/storage/core/libs/diagnostics/critical_events.cpp
index 0714858302d..d595cdcab1d 100644
--- a/cloud/storage/core/libs/diagnostics/critical_events.cpp
+++ b/cloud/storage/core/libs/diagnostics/critical_events.cpp
@@ -50,8 +50,8 @@ TString ReportCriticalEvent(
     fullMessage << "CRITICAL_EVENT:" << sensorName;
     if (message) {
         fullMessage << ":" << message;
-        Cerr << fullMessage << Endl;
     }
+    Cerr << fullMessage << Endl;
 
     return fullMessage;
 }

From 80cb5e3464a4c402061c39102697dd282ccf1bb7 Mon Sep 17 00:00:00 2001
From: Kirill Pleshivtsev <drbasic@yandex-team.ru>
Date: Thu, 14 Mar 2024 14:28:28 +0700
Subject: [PATCH 2/3] Make writing almost atomic

---
 cloud/storage/core/libs/diagnostics/critical_events.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/cloud/storage/core/libs/diagnostics/critical_events.cpp b/cloud/storage/core/libs/diagnostics/critical_events.cpp
index d595cdcab1d..facf61b5c2d 100644
--- a/cloud/storage/core/libs/diagnostics/critical_events.cpp
+++ b/cloud/storage/core/libs/diagnostics/critical_events.cpp
@@ -51,7 +51,13 @@ TString ReportCriticalEvent(
     if (message) {
         fullMessage << ":" << message;
     }
-    Cerr << fullMessage << Endl;
+
+    if (!verifyDebug || message) {
+        // Write message and \n in one call. This will reduce the chance of
+        // shuffling with writings of other threads.
+        Cerr << fullMessage + '\n';
+        Cerr.Flush();
+    }
 
     return fullMessage;
 }

From 1c2d520b00e2cdf8477f28e5379d5f3cd758e623 Mon Sep 17 00:00:00 2001
From: Kirill Pleshivtsev <drbasic@yandex-team.ru>
Date: Thu, 28 Mar 2024 15:43:09 +0700
Subject: [PATCH 3/3] Use global logger

---
 cloud/blockstore/libs/daemon/common/bootstrap.cpp    |  1 +
 cloud/filestore/libs/daemon/common/bootstrap.cpp     |  3 ++-
 .../core/libs/diagnostics/critical_events.cpp        | 12 ++++++++++--
 .../storage/core/libs/diagnostics/critical_events.h  |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/cloud/blockstore/libs/daemon/common/bootstrap.cpp b/cloud/blockstore/libs/daemon/common/bootstrap.cpp
index beb1692108c..ca6d13c75df 100644
--- a/cloud/blockstore/libs/daemon/common/bootstrap.cpp
+++ b/cloud/blockstore/libs/daemon/common/bootstrap.cpp
@@ -199,6 +199,7 @@ void TBootstrapBase::Init()
 
     BootstrapLogging = CreateLoggingService("console", logSettings);
     Log = BootstrapLogging->CreateLog("BLOCKSTORE_SERVER");
+    SetCriticalEventsLog(Log);
     Configs->Log = Log;
     STORAGE_INFO("NBS server version: " << GetFullVersionString());
 
diff --git a/cloud/filestore/libs/daemon/common/bootstrap.cpp b/cloud/filestore/libs/daemon/common/bootstrap.cpp
index fb5918ce7f2..e189d0c9be9 100644
--- a/cloud/filestore/libs/daemon/common/bootstrap.cpp
+++ b/cloud/filestore/libs/daemon/common/bootstrap.cpp
@@ -11,13 +11,13 @@
 #include <cloud/filestore/libs/server/server.h>
 #include <cloud/filestore/libs/storage/core/config.h>
 #include <cloud/filestore/libs/storage/init/actorsystem.h>
-
 #include <cloud/storage/core/libs/common/scheduler.h>
 #include <cloud/storage/core/libs/common/task_queue.h>
 #include <cloud/storage/core/libs/common/thread_pool.h>
 #include <cloud/storage/core/libs/common/timer.h>
 #include <cloud/storage/core/libs/daemon/mlock.h>
 #include <cloud/storage/core/libs/diagnostics/cgroup_stats_fetcher.h>
+#include <cloud/storage/core/libs/diagnostics/critical_events.h>
 #include <cloud/storage/core/libs/diagnostics/logging.h>
 #include <cloud/storage/core/libs/diagnostics/monitoring.h>
 #include <cloud/storage/core/libs/diagnostics/stats_updater.h>
@@ -99,6 +99,7 @@ TBootstrapCommon::TBootstrapCommon(
     BootstrapLogging->Start();
 
     Log = BootstrapLogging->CreateLog(logComponent);
+    SetCriticalEventsLog(Log);
 }
 
 TBootstrapCommon::~TBootstrapCommon()
diff --git a/cloud/storage/core/libs/diagnostics/critical_events.cpp b/cloud/storage/core/libs/diagnostics/critical_events.cpp
index facf61b5c2d..40d245e93a6 100644
--- a/cloud/storage/core/libs/diagnostics/critical_events.cpp
+++ b/cloud/storage/core/libs/diagnostics/critical_events.cpp
@@ -1,7 +1,7 @@
 #include "critical_events.h"
-
 #include "public.h"
 
+#include <library/cpp/logger/log.h>
 #include <library/cpp/monlib/dynamic_counters/counters.h>
 
 #include <util/string/builder.h>
@@ -13,11 +13,17 @@ using namespace NMonitoring;
 namespace {
 
 NMonitoring::TDynamicCountersPtr CriticalEvents;
+TLog Log;
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void SetCriticalEventsLog(TLog log)
+{
+    Log = std::move(log);
+}
+
 void InitCriticalEventsCounter(NMonitoring::TDynamicCountersPtr counters)
 {
     CriticalEvents = std::move(counters);
@@ -52,7 +58,9 @@ TString ReportCriticalEvent(
         fullMessage << ":" << message;
     }
 
-    if (!verifyDebug || message) {
+    if (Log.IsNotNullLog()) {
+        Log.AddLog("%s", fullMessage.c_str());
+    } else {
         // Write message and \n in one call. This will reduce the chance of
         // shuffling with writings of other threads.
         Cerr << fullMessage + '\n';
diff --git a/cloud/storage/core/libs/diagnostics/critical_events.h b/cloud/storage/core/libs/diagnostics/critical_events.h
index 9777a7b38b6..2754c38bde5 100644
--- a/cloud/storage/core/libs/diagnostics/critical_events.h
+++ b/cloud/storage/core/libs/diagnostics/critical_events.h
@@ -15,6 +15,7 @@ namespace NCloud {
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void SetCriticalEventsLog(TLog log);
 void InitCriticalEventsCounter(NMonitoring::TDynamicCountersPtr counters);
 
 TString ReportCriticalEvent(