Is it recommended to turn on System Proxy and Enhanced Mode at the same time?

meowzz

Background:

I need to turn on Enhanced mode because some CLI tools I use don't respect system proxy settings.
It runs without any problem now, current status: System Proxy is OFF, Enhanced Mode is ON.

My question:
Is it recommended to turn on both System Proxy and Enhanced Mode? Will it reduce the load on the VIF thus improving performance? My guts tell me this is not the case as the VIF is taking over all traffic so even if the packets went through the proxy, they will reach the VIF again, even if Surge has some way to tell these packets are already processed by the proxy part, it is already processing the packet again(from kernel space to user space?) so I guess there's no benefit turning them both on at the same time.

Really appreciate it if the team could share the best practice here, thanks in advance!

SurgeTeam

It is recommended to turn them on at the same time, applications that support Proxy will use the proxy, and the remaining applications will be taken over by VIF.

meowzz

SurgeTeam Thanks, very clear answer, perhaps we can consider adding this to the documentation?

meowzz

SurgeTeam and if I may ask, how is this achieved?
VIF should be the outgoing interface for all traffic because the routing table is setup this way.
The SOCKS proxy should be a step before the routing right? So the packets go through the proxy and handled by Surge, then they're still routed to the VIF, and at this point of time, even if Surge has a way to identify this has already been processed, it has already used the processing power(because it reached the VIF)...
How is this helping with performance?
Thanks!

SurgeTeam

meowzz When the enhanced mode is activated, Surge will record the current main interface and force requests to be sent from the main interface when processing subsequent requests.

meowzz

SurgeTeam Yea I got this part I think. Let me rephrase my question:
Packet flow:

Turn on both:
app -> socks going to surge(Surge magic happens here like packet inspection etc) -> routed to VIF because (almost) all traffic should be routed to VIF when enhanced mode is on -> VIF forwards it to the main interface

Turn on Enhanced mode only:
app -> routed to VIF because (almost) all traffic should be routed to VIF when enhanced mode is on(Surge magic happens here like packet inspection etc) -> VIF forward it to main interface

Am I right about this flow? If this is correct, in both way, the packet ends up in VIF and forward to main interface, just a matter of when the Surge magic happens. Is it because it costs more to do Surge magic in the VIF than in the SOCKS?

SurgeTeam

meowzz No. When requesting to be taken over by a proxy, it communicates directly with Surge through the loopback socket, which has nothing to do with VIF.

meowzz

SurgeTeam Wow that is the missing piece! Thanks!!!