4 ms·
What's that userspace qos thing? You can already set DSCP, so is this more like setting the actual shaping/policing policies for your sockets?
by knorker 5y ago
What's that userspace qos thing? You can already set DSCP, so is this more like setting the actual shaping/policing policies for your sockets?
- hinkley 5y agoWould that be avoiding system call round trip overhead perhaps? I wonder how some of these tools will change due to progress on io_uring and similar idioms. Batching system calls to amortize the cost.
- knorker 5y agoHmm, seems unlikely, since at least for TCP this is just one syscall per connection. Syscalls are not that expensive.
- jeffbee 5y agoI don't know if this is what they were driving at but there are tons of useful things that you can't do in the sockets API like selectively up- or down-grading DSCP for a subset of TCP ACKs. Linux also does not come out of the box with DSCP reflection for the SYN+ACK, or at least it didn't until 5.10. Google prodkernel had this feature for at least a decade prior. https://lwn.net/Articles/831194/ https://lwn.net/Articles/831194/