l2-poisson-load-latency.lua

local dpdk      = require "dpdk"
local memory    = require "memory"
local ts        = require "timestamping"
local device    = require "device"
local filter    = require "filter"
local stats     = require "stats"
local timer     = require "timer"
local histogram = require "histogram"


local PKT_SIZE = 60

function master(...)
    local txPort, rxPort, rate = tonumberall(...)
    if not txPort or not rxPort then
        errorf("usage: txPort rxPort [rate (Mpps)]")
    end
    rate = rate or 2
    local txDev = device.config(txPort, 2, 2)
    local rxDev = device.config(rxPort, 2, 2)
    device.waitForLinks()
    dpdk.launchLua("loadSlave", txDev, rxDev, txDev:getTxQueue(0), rate, PKT_SIZE)
    dpdk.launchLua("timerSlave", txDev:getTxQueue(1), rxDev:getRxQueue(1), PKT_SIZE)
    dpdk.waitForSlaves()
end

function loadSlave(dev, rxDev, queue, rate, size)
    local mem = memory.createMemPool(function(buf)
        buf:getEthernetPacket():fill{
            ethType = 0x1234
        }
    end)
    rxDev:l2Filter(0x1234, filter.DROP)
    local bufs = mem:bufArray()
    local rxStats = stats:newDevRxCounter(rxDev, "plain")
    local txStats = stats:newManualTxCounter(dev, "plain")
    while dpdk.running() do
        bufs:alloc(size)
        for _, buf in ipairs(bufs) do
            -- this script uses Mpps instead of Mbit (like the other scripts)
            buf:setDelay(poissonDelay(10^10 / 8 / (rate * 10^6) - size - 24))
            --buf:setRate(rate)
        end
        txStats:updateWithSize(queue:sendWithDelay(bufs), size)
        rxStats:update()
        --txStats:update()
    end
    rxStats:finalize()
    txStats:finalize()
end

function timerSlave(txQueue, rxQueue, size)
    local timestamper = ts:newTimestamper(txQueue, rxQueue)
    local hist = histogram:new()
    -- wait for a second to give the other task a chance to start
    dpdk.sleepMillis(1000)
    local rateLimiter = timer:new(0.001)
    while dpdk.running() do
        rateLimiter:reset()
        hist:update(timestamper:measureLatency(size))
        rateLimiter:busyWait()
    end
    hist:print()
    hist:save("histogram.csv")
end