Downtime for failover is too long on Linux

Hi experts,

I'm new to SQL Server. Nowadays I want to use SQL Server on Linux. and I tested the failover SQL Server on Linux and Windows Server. 

And I found out that downtime for failover is too long on linux.

Env for windows

OS : windows server 2016 with AD (3node)

SQL : SQL Server 2017

Failover Downtime : 10s

Env for Linux

OS : ubuntu 16.04 with pacemaker (3node)

SQL : SQL Server 2017

Downtime : 40s(I tested it on centos again and I got the same result)

So I doubt thepacemaker configuration or something on Linux. I don't know where I should see.

I followed the document (https://docs.microsoft.com/en-us/sql/linux/sql-server-linux-create-availability-group?view=sql-server-linux-2017)

Could you give me some advice? Do you need more information to solve or check? Tell me.

Thank you.