From 86a7f1d97b14b5f44413d5ac0b44899dcdc8a4dd Mon Sep 17 00:00:00 2001
From: Maxim Akhmedov <max42@yandex-team.ru>
Date: Thu, 23 Jan 2020 14:22:06 +0300
Subject: [PATCH] Make system log engine customizable via config.

---
 dbms/src/Interpreters/SystemLog.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/dbms/src/Interpreters/SystemLog.cpp b/dbms/src/Interpreters/SystemLog.cpp
index 6eb0ce69f4e..78029eba576 100644
--- a/dbms/src/Interpreters/SystemLog.cpp
+++ b/dbms/src/Interpreters/SystemLog.cpp
@@ -31,8 +31,15 @@ std::shared_ptr<TSystemLog> createSystemLog(
 
     String database = config.getString(config_prefix + ".database", default_database_name);
     String table = config.getString(config_prefix + ".table", default_table_name);
-    String partition_by = config.getString(config_prefix + ".partition_by", "toYYYYMM(event_date)");
-    String engine = "ENGINE = MergeTree PARTITION BY (" + partition_by + ") ORDER BY (event_date, event_time)";
+
+    String engine;
+    if (config.has(config_prefix + ".custom_engine"))
+        engine = config.getString(config_prefix + ".custom_engine");
+    else
+    {
+        String partition_by = config.getString(config_prefix + ".partition_by", "toYYYYMM(event_date)");
+        engine = "ENGINE = MergeTree PARTITION BY (" + partition_by + ") ORDER BY (event_date, event_time) SETTINGS index_granularity = 1024";
+    }
 
     size_t flush_interval_milliseconds = config.getUInt64(config_prefix + ".flush_interval_milliseconds", DEFAULT_SYSTEM_LOG_FLUSH_INTERVAL_MILLISECONDS);