From 40a48c5670554a1dac98f69ea720b0cbecff3249 Mon Sep 17 00:00:00 2001
From: Nikolai Kochetov <nik-kochetov@yandex-team.ru>
Date: Fri, 18 Feb 2022 18:32:04 +0000
Subject: [PATCH] Enable async writes to S3.

---
 src/Disks/S3/DiskS3.cpp | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/src/Disks/S3/DiskS3.cpp b/src/Disks/S3/DiskS3.cpp
index 8aa4f8f0dff..b7e752edafd 100644
--- a/src/Disks/S3/DiskS3.cpp
+++ b/src/Disks/S3/DiskS3.cpp
@@ -262,21 +262,20 @@ std::unique_ptr<WriteBufferFromFileBase> DiskS3::writeFile(const String & path,
     LOG_TRACE(log, "{} to file by path: {}. S3 path: {}",
               mode == WriteMode::Rewrite ? "Write" : "Append", backQuote(metadata_disk->getPath() + path), remote_fs_root_path + blob_name);
 
-    /// FIXME -- thread pool lead to obscure segfaults
-    /// ScheduleFunc schedule = [pool = &getThreadPoolWriter(), thread_group = CurrentThread::getGroup()](auto callback)
-    /// {
-    ///     pool->scheduleOrThrow([callback = std::move(callback), thread_group]()
-    ///     {
-    ///         if (thread_group)
-    ///             CurrentThread::attachTo(thread_group);
+    ScheduleFunc schedule = [pool = &getThreadPoolWriter(), thread_group = CurrentThread::getGroup()](auto callback)
+    {
+        pool->scheduleOrThrow([callback = std::move(callback), thread_group]()
+        {
+            if (thread_group)
+                CurrentThread::attachTo(thread_group);
 
-    ///         SCOPE_EXIT_SAFE(
-    ///             if (thread_group)
-    ///                 CurrentThread::detachQueryIfNotDetached();
-    ///         );
-    ///         callback();
-    ///     });
-    /// };
+            SCOPE_EXIT_SAFE(
+                if (thread_group)
+                    CurrentThread::detachQueryIfNotDetached();
+            );
+            callback();
+        });
+    };
 
     auto s3_buffer = std::make_unique<WriteBufferFromS3>(
         settings->client,