3 ms·

Anyone know roughly where to look for in terms of potential bottlenecks? I’m running my server on an rpi4 and sometimes feel like I’m not getting great speeds t

by heyoni 7y ago

Anyone know roughly where to look for in terms of potential bottlenecks? I’m running my server on an rpi4 and sometimes feel like I’m not getting great speeds to my home VPN server. I did do my due diligence by wiring it directly through Ethernet but I suspect my router (google WiFi) may be slowing things down.

mikl 7y ago
Number one would probably be to ensure the rpi has a good cabled connection to the router (and make sure it uses it instead of WiFi). VPN connections going back and forth over WiFi would slow things down. Next bottleneck would probably be CPU. Check if the CPU is being maxed out or throttled when you’re using the VPN.
- heyoni 7y ago
  I don't think I ever even set up wifi, but I'm going to follow another reply that suggested tools for testing the real speed that the rpi is getting.
irq 7y ago
Does your rpi4 have proper cooling? Unlike all past rpis, the stock cooling on the rpi4 is easily overwhelmed by even slight load, and it drastically slows down in that situation.
- heyoni 7y ago
  I put on an aluminum case for passive cooling and now it runs around 48 celsius as opposed to 70+ before. That should be good right?
  - irq 7y ago
    Does the case make direct metal to metal contact with all 3 major heat producing chips on the rpi4? IIRC, the chip related to ethernet gets very, very hot in use and not all metal rpi4 cases actually make contact with it.
    - heyoni 7y ago
      It's this case here I've got: https://flirc.tv/more/raspberry-pi-4-case https://flirc.tv/more/raspberry-pi-4-case It looks like it does...maybe I should stick my finger in there. I should probably monitor my CPU history a bit better, I'm just relying on pihole's panel at the moment.
simcop2387 7y ago
Another thing to check would be to use ethtool to see what speed the raspberry pi ethernet port is reaching with your router. This wasn't on a pi, but it'll look similar. Look at the Speed: line mostly, it'll say either 100MBit or 1000MBit depending on your router (some still only have 100MBit switches). Also look for Duplex: Full, I've had sometimes a config get set badly where it'll be half duplex and cause speed issues, usually due to a bad cable initially causing errors and bad autodetection. > % sudo ethtool enp4s0 Settings for enp4s0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 1 Transceiver: internal Auto-negotiation: on MDI-X: off (auto) Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000007 (7) drv probe link Link detected: yes

by heyoni 7y ago

mikl 7y ago

Number one would probably be to ensure the rpi has a good cabled connection to the router (and make sure it uses it instead of WiFi). VPN connections going back and forth over WiFi would slow things down. Next bottleneck would probably be CPU. Check if the CPU is being maxed out or throttled when you’re using the VPN.

heyoni 7y ago
I don't think I ever even set up wifi, but I'm going to follow another reply that suggested tools for testing the real speed that the rpi is getting.

irq 7y ago

Does your rpi4 have proper cooling? Unlike all past rpis, the stock cooling on the rpi4 is easily overwhelmed by even slight load, and it drastically slows down in that situation.

heyoni 7y ago
I put on an aluminum case for passive cooling and now it runs around 48 celsius as opposed to 70+ before. That should be good right?
- irq 7y ago
  Does the case make direct metal to metal contact with all 3 major heat producing chips on the rpi4? IIRC, the chip related to ethernet gets very, very hot in use and not all metal rpi4 cases actually make contact with it.
  - heyoni 7y ago
    It's this case here I've got: https://flirc.tv/more/raspberry-pi-4-case https://flirc.tv/more/raspberry-pi-4-case It looks like it does...maybe I should stick my finger in there. I should probably monitor my CPU history a bit better, I'm just relying on pihole's panel at the moment.

simcop2387 7y ago

Another thing to check would be to use ethtool to see what speed the raspberry pi ethernet port is reaching with your router. This wasn't on a pi, but it'll look similar. Look at the Speed: line mostly, it'll say either 100MBit or 1000MBit depending on your router (some still only have 100MBit switches). Also look for Duplex: Full, I've had sometimes a config get set badly where it'll be half duplex and cause speed issues, usually due to a bad cable initially causing errors and bad autodetection. > % sudo ethtool enp4s0 Settings for enp4s0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 1 Transceiver: internal Auto-negotiation: on MDI-X: off (auto) Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000007 (7) drv probe link Link detected: yes