VPN + cake SQM

hello i would like to use vpn but what should be the exact overhead

should i put like my br-lan

this is my output in vdsl2

thank you

qdisc cake 801a: dev tun0 root refcnt 2 bandwidth 32Mbit diffserv4 dual-dsthost nonat nowash ingress no-ack-filter split-gso rtt 100ms noatm overhead 44
 Sent 1019574 bytes 3937 pkt (dropped 0, overlimits 438 requeues 0)
 backlog 0b 0p requeues 0
 memory used: 12794b of 4Mb
 capacity estimate: 32Mbit
 min/max network layer size:           40 /    1370
 min/max overhead-adjusted size:       84 /    1414
 average network hdr offset:            0

                   Bulk  Best Effort        Video        Voice
  thresh          2Mbit       32Mbit       16Mbit        8Mbit
  target            9ms          5ms          5ms          5ms
  interval        104ms        100ms        100ms        100ms
  pk_delay        678us         27us          0us         79us
  av_delay        221us          0us          0us          5us
  sp_delay         16us          0us          0us          2us
  backlog            0b           0b           0b           0b
  pkts              500           16            0         3421
  bytes          556514         2826            0       460234
  way_inds            0            0            0            0
  way_miss            3            1            0            3
  way_cols            0            0            0            0
  drops               0            0            0            0
  marks               0            0            0            0
  ack_drop            0            0            0            0
  sp_flows            0            0            0            0
  bk_flows            1            0            0            1
  un_flows            0            0            0            0
  max_len          8220         1213            0         1250
  quantum           300          976          488          300