Internet speed issue

Hi,
In my internal network I have shadowsocks server (android).
I run openWRT with client and forward all traffic over the that server.
Network has very low load. One pc with web traffic.
I face internet speed issue. It literally makes half of my speed.
I thought it was because encryption. So made changes and build it to not encrypt. Anyway traffic is local and it does not matter.
No impact on speed... I tried fast open and etc... But same...
I run almost default config... Please advise.

config server 'sss0'
option server_port '1886'
option server '192.0.0.2'
option method 'none'
option password 'none'

config ss_tunnel
option server 'sss0'
option local_address '0.0.0.0'
option local_port '8053'
option tunnel_address '1.1.1.1:53'
option verbose '1'
option user 'shadowsocks'
option mode 'tcp_and_udp'

config ss_redir 'ssr0'
option server 'sss0'
option local_address '0.0.0.0'
option local_port '1100'
option loglevel 'verbose'
option verbose '1'
option user 'shadowsocks'
option reuse_port '1'
option mode 'tcp_and_udp'

config ss_rules 'ss_rules'
option src_default 'checkdst'
option dst_default 'forward'
option redir_udp 'ssr0'
option redir_tcp 'ssr0'
option local_default 'forward'

Start by reproducing the reported speed difference using the supplied OpenWrt Shadowsocks configuration, comparing direct traffic with traffic through ssr0. No source file or test is named; the work is complete only when the throughput cause is identified and a verified configuration or code fix is available.