【入门夯实】慢调用日志：超阈值收集与分类统计

local function onQuery(source)
    local t0 = os.clock()
    doQuery(source)
end

local SLOW_MS = 50
local slowStat = {}
local function timedQuery(source, fn)
    local t0 = os.clock()
    fn()
    local cost = (os.clock() - t0) * 1000
    if cost >= SLOW_MS then
        slowStat[source] = (slowStat[source] or 0) + 1
        print("慢调用 " .. source .. " " .. string.format("%.1f", cost) .. "ms")
    end
end
local function reportTop()
    local rows = {}
    for k, v in pairs(slowStat) do
        rows[#rows + 1] = { src = k, cnt = v }
    end
    table.sort(rows, function(a, b)
        return a.cnt > b.cnt
    end
    )
    for i = 1, math.min(10, #rows) do
        sendmsg(nil, 1, "慢调用第" .. i .. "名 " .. rows[i].src ..
            " 累计 " .. rows[i].cnt .. " 次")
    end
end

timedQuery("rank_query", function()
    rebuildRank()
end
)

local THRESH = { query = 50, write = 200, notify = 300 }
local function isSlow(kind, cost)
    return cost >= (THRESH[kind] or 100)
end