Slow Samba4 write performances

Did you enable " tcp_bbr " kernel module?
I found that my router(Newifi-D2) suffers bad read performace when enable tcp_bbr.

My openwrt version is 19.07.x and the samba server is 4.11.

I find my situation solution:
By adding line " net.core.default_qdisc=fq" to file /etc/sysctl.d/12-tcp-bbr.conf, the problem disappears.