From: Eric Dumazet <eduma...@google.com> Date: Mon, 10 Jun 2019 20:03:34 -0700
> Adding delays to TCP flows is crucial for studying behavior > of TCP stacks, including congestion control modules. > > Linux offers netem module, but it has unpractical constraints : > - Need root access to change qdisc > - Hard to setup on egress if combined with non trivial qdisc like FQ > - Single delay for all flows. > > EDT (Earliest Departure Time) adoption in TCP stack allows us > to enable a per socket delay at a very small cost. > > Networking tools can now establish thousands of flows, each of them > with a different delay, simulating real world conditions. > > This requires FQ packet scheduler or a EDT-enabled NIC. > > This patchs adds TCP_TX_DELAY socket option, to set a delay in > usec units. ... > Signed-off-by: Eric Dumazet <eduma...@google.com> Applied to net-next and build testing. Thanks.
