From cd9cc4c5057581970db4f8107c2a86ff0b24f4e2 Mon Sep 17 00:00:00 2001
From: Alexander Turenko <alexander.turenko@tarantool.org>
Date: Fri, 19 Oct 2018 22:05:02 +0300
Subject: [PATCH] xlog: fix sync_is_async xlog option

The behaviour change was introduced in cda3cb55: sync_is_async option
was forgotten to be updated from xdir; sync_interval was forgotten too,
but was restored in 1900c58b.

The commit fixes the performance regression around 6-14% for average RPS
on default nosqlbench workload with 30 seconds duration. The additional
information about benchmarking can be found in #3747.

Thanks to Vladimir Davydov (@locker) for the investigation of the
cda3cb55 changes.

Closes #3747
---
 src/box/xlog.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/box/xlog.c b/src/box/xlog.c
index de5e52f743..90157d8399 100644
--- a/src/box/xlog.c
+++ b/src/box/xlog.c
@@ -971,8 +971,10 @@ xdir_create_xlog(struct xdir *dir, struct xlog *xlog,
 	if (xlog_create(xlog, filename, dir->open_wflags, &meta) != 0)
 		return -1;
 
-	/* set sync interval from xdir settings */
+	/* Inherit xdir settings. */
+	xlog->sync_is_async = dir->sync_is_async;
 	xlog->sync_interval = dir->sync_interval;
+
 	/* free file cache if dir should be synced */
 	xlog->free_cache = dir->sync_interval != 0 ? true: false;
 	xlog->rate_limit = 0;
-- 
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