Add switch to disable TCP_NODELAY #112
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This in an attempt quell CPU usage, since PCCW is having issues when
their {N} number of routers all start RTR sessions at the same time.
A `perf` of the system suggests all of the CPU is going to sending
TCP traffic, and since golang enables NO_DELAY (infamously?) by
default, this is a good smoking gun, since this would imply that
stayrtr is sending 1 TCP packet per RTR PDU, something that would
indeed cause a lot of CPU usage in aggergate!
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Yup |
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It's actually a switch to enable NODELAY, but it is still morning so we'll let that slide ;-) |
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This in an attempt quell CPU usage, since PCCW is having issues when their {N} number of routers all start RTR sessions at the same time.
A
perfof the system suggests all of the CPU is going to sending TCP traffic, and since golang enables NO_DELAY (infamously?) by default, this is a good smoking gun, since this would imply that stayrtr is sending 1 TCP packet per RTR PDU, something that would indeed cause a lot of CPU usage in aggergate!This patch was written some time ago, but reports from PCCW states that this does actually help their network a noticeable amount, So I think this is a worthy switch to be introduced