9.14.0rc3 has about half performance lost than 9.12.4

I have tested the performance of the new 9.14.0rc3 and compare with 9.12.4. the QPS of 9.14 have about 45% lost than that of 9.12.

the testing result for 9.12.4,

• Queries per second: 96571.134918
• Queries per second: 96654.148453
• Queries per second: 95680.651623

which for 9.14.0rc3,

• Queries per second: 51983.847508
• Queries per second: 52680.816235
• Queries per second: 52310.111644

I'm not sure if my configure options for build BIND had missed something.

my testbed environment is,

1. server hardware

• CPU, AMD Athlon(tm) X4 845 Quad Core Processor
• Mem, 8GBytes

2. system, Fedora29 x86_64

• dnsperf, version 2.2.1

3. configure options,

• BIND 9.12.4 <id:079c3eb>, --enable-threads --with-libjson
• BIND 9.14.0rc3 (Stable Release) <id:e01057f>, defaults

4. client is on the same host with server
5. named.conf

options {
	directory "/var/named";
	recursion no;
};

logging {
	channel default {
		file "default.log" versions 10 size 10m;
		print-category yes;
		print-severity yes;
		print-time yes;
		buffered no;
	};
	channel general {
		file "general.log" versions 10 size 10m;
		print-category yes;
		print-severity yes;
		print-time yes;
		buffered no;
	};
	channel queries {
		file "query.log" versions 10 size 10m;
		print-category yes;
		print-severity yes;
		print-time yes;
		buffered no;
	};
	category default { default; };
	category general { general; };
	// category queries { queries; };
};

zone "test.com" {
	type master;
	file "test.com";
};

6. zonefile,

$TTL 86400
@	IN	SOA	a.test.com. postmaster.test.com. (
	2019031901
	3600
	600
	2419200
	300 )
	IN	NS	a.test.com.
a.test.com.	IN	A	192.168.3.11

$ORIGIN test.com.
$INCLUDE 1m

# cat /var/named/1m

name000000	IN	A	10.0.0.1
name000001	IN	A	10.0.0.1
...
name999999	IN	A	10.0.0.1

7. the input data file for dnsperf,

name000000.test.com. A
name000001.test.com. A
...
name999999.test.com. A

8. the command line of dnsperf,

dnsperf -s 192.168.3.11 -d qp -l 60