I'd even go as far as claiming that on reliable wired connections (like between cloudflare and your backend) HTTP/2 is superior to HTTP/3. Choosing HTTP/3 for that part of the journey would be a downgrade
Is the protocol inherently inferior in situations like that, or is this because we've spent decades optimizing for TCP and building into kernels and hardware? If we imagine a future where QUIC gets that kind of support, will it still be a downgrade?
At the very least, the benefits of QUIC are very very dubious for low RTT connections like inside a datacenter, especially when you're losing a bunch of hardware support and moving a fair bit of actual work to userspace where threads need to be scheduled etc. On the other hand Cloudflare to backend is not necessarily low RTT and likely has nonzero congestion.
With that said, I am 100% in agreement that the primary benefits of QUIC in most cases would be between client and CDN, whereas the costs are comparable at every hop.
Also, within a single server, you should not use HTTP between your frontend nginx and your application server - use FastCGI or SCGI instead, as they preserve metadata (like client IP) much better. You can also use them over the network within a datacenter, in theory.
So? Those protocols work fine within the reliable low latency network of a datacenter.
I'd even go as far as claiming that on reliable wired connections (like between cloudflare and your backend) HTTP/2 is superior to HTTP/3. Choosing HTTP/3 for that part of the journey would be a downgrade
Is the protocol inherently inferior in situations like that, or is this because we've spent decades optimizing for TCP and building into kernels and hardware? If we imagine a future where QUIC gets that kind of support, will it still be a downgrade?
At the very least, the benefits of QUIC are very very dubious for low RTT connections like inside a datacenter, especially when you're losing a bunch of hardware support and moving a fair bit of actual work to userspace where threads need to be scheduled etc. On the other hand Cloudflare to backend is not necessarily low RTT and likely has nonzero congestion.
With that said, I am 100% in agreement that the primary benefits of QUIC in most cases would be between client and CDN, whereas the costs are comparable at every hop.
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Also, within a single server, you should not use HTTP between your frontend nginx and your application server - use FastCGI or SCGI instead, as they preserve metadata (like client IP) much better. You can also use them over the network within a datacenter, in theory.