OpenVPN and Squid limited on VPS (OpenVZ)

Kiryu

I have two vps, one on OVH with KVM, the second on another hosting with OpenVZ. On OVH the speed is ok with squid and openvpn, i reach 100mbit (max speed of my connection), but i have a problem with the second vps. My internet speed is limited to 30mbit when i use Squid and OpenVPN, but only in browser (Chrome and Firefox). If i use torrent, Steam, IDM (Internet Download Manager) or other, i reach the max speed. I have asked to my hosting provider, he have said "It's a bug of OpenVZ, you don't have this problem on OVH because is virtualized with KVM".
It's true?

OpenVPN conf per both VPS

port 62826
proto udp
dev tun
user nobody
group nogroup
persist-key
persist-tun
keepalive 10 120
topology subnet
server 10.8.0.0 255.255.255.0
ifconfig-pool-persist ipp.txt
push "dhcp-option DNS 1.0.0.1"
push "dhcp-option DNS 1.1.1.1"
push "redirect-gateway def1 bypass-dhcp"
dh none
ecdh-curve prime256v1
tls-crypt tls-crypt.key 0
crl-verify crl.pem
ca ca.crt
cert server_hVVe1BJQj2YiiRCh.crt
key server_hVVe1BJQj2YiiRCh.key
auth SHA256
cipher AES-128-GCM
ncp-ciphers AES-128-GCM
tls-server
tls-version-min 1.2
tls-cipher TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256
status /var/log/openvpn/status.log
verb 0

Even for squid the conf is the same for both VPS. Default conf, i have only changed the default port and added these lines:

acl kiryu src MY IP
http_access allow kiryu
tcp_outgoing_address SERVER IP (CENSORED)
udp_outgoing_address SERVER IP (CENSORED)
visible_hostname kiryu
access_log none
cache_store_log none
cache_log /dev/null
httpd_suppress_version_string on
dns_v4_first on

Thanks in advance for the help