Need help regarding wireless upload spikes on 5ghz wireless

I have openwrt 19.07.7 on tp-link archer c20 v4 using MediaTek MT7628AN as 2.4ghz wireless and MediaTek MT7610E as 5 ghz wireless... i m on 30/30 fiber.

i m seeing problem with 5ghz wireless with upload spikes... i m using script from https://github.com/dlakelan/routerperf with veth enabled...

problem i see:

  1. 5ghz wireless goes higher than what i have limited initially(this happened in other scripts too) and while this happens the ping goes very bad...

DSL reports for:
wired:

wireless(2.4 ghz):
http://www.dslreports.com/speedtest/67663457

wireless(5 ghz)
http://www.dslreports.com/speedtest/67663499

wireless config:

config wifi-device 'radio0'
	option type 'mac80211'
	option channel '11'
	option hwmode '11g'
	option path 'platform/10300000.wmac'
	option htmode 'HT20'
	option legacy_rates '0'

config wifi-iface 'default_radio0'
	option device 'radio0'
	option network 'lan'
	option mode 'ap'
	option key 'karimalama'
	option ssid 'karima'
	option encryption 'psk2'

config wifi-device 'radio1'
	option type 'mac80211'
	option channel '36'
	option hwmode '11a'
	option path 'pci0000:00/0000:00:00.0/0000:01:00.0'
	option legacy_rates '0'
	option txpower '20'
	option htmode 'HT40'

config wifi-iface 'default_radio1'
	option device 'radio1'
	option network 'lan'
	option mode 'ap'
	option key 'mozyeslama'
	option ssid 'gaming'
	option encryption 'psk2'

and my cat /tmp/run/hostapd-phy0.conf and cat /tmp/run/hostapd-phy1.conf looks like

root@OpenWrt:~# cat /tmp/run/hostapd-phy0.conf
driver=nl80211
logger_syslog=127
logger_syslog_level=2
logger_stdout=127
logger_stdout_level=2
hw_mode=g
supported_rates=60 90 120 180 240 360 480 540
basic_rates=60 120 240
beacon_int=100
channel=11



ieee80211n=1
ht_coex=0
ht_capab=[SHORT-GI-20][SHORT-GI-40][TX-STBC][RX-STBC1]

interface=wlan0
ctrl_interface=/var/run/hostapd
ap_isolate=1
bss_load_update_period=60
chan_util_avg_period=600
disassoc_low_ack=1
preamble=1
wmm_enabled=1
ignore_broadcast_ssid=0
uapsd_advertisement_enabled=1
utf8_ssid=1
multi_ap=0
wpa_passphrase=karimalama
auth_algs=1
wpa=2
wpa_pairwise=CCMP
ssid=karima
bridge=br-lan
wpa_disable_eapol_key_retries=0
wpa_key_mgmt=WPA-PSK
okc=0
disable_pmksa_caching=1
bssid=0c:80:63:fe:2c:41


root@OpenWrt:~# cat /tmp/run/hostapd-phy1.conf
driver=nl80211
logger_syslog=127
logger_syslog_level=2
logger_stdout=127
logger_stdout_level=2
hw_mode=a
beacon_int=100
channel=36



ieee80211n=1
ht_coex=0
ht_capab=[HT40+][SHORT-GI-20][SHORT-GI-40][RX-STBC1]

interface=wlan1
ctrl_interface=/var/run/hostapd
ap_isolate=1
bss_load_update_period=60
chan_util_avg_period=600
disassoc_low_ack=1
preamble=1
wmm_enabled=1
ignore_broadcast_ssid=0
uapsd_advertisement_enabled=1
utf8_ssid=1
multi_ap=0
wpa_passphrase=mozyeslama
auth_algs=1
wpa=2
wpa_pairwise=CCMP
ssid=gaming
bridge=br-lan
wpa_disable_eapol_key_retries=0
wpa_key_mgmt=WPA-PSK
okc=0
disable_pmksa_caching=1
bssid=0c:80:63:fe:2c:42