【Lua实战】LRU 缓存：玩家资料缓存的淘汰策略

local CAP = 512
local cache = {}
local function put(nm, actor)
    local p = class(actor)
    cache[nm] = {
        lv = getbaseinfo(p, 6),
        gn = getmyguild(p),
        t = os.time(),
    }
end
local function get(nm)
    local e = cache[nm]
    if e == nil then return nil end
    if os.time() - e.t > 300 then
        cache[nm] = nil
        return nil
    end
    e.t = os.time()
    return e
end

local hit, req = 0, 0
local function trim()
    local keys = {}
    for nm, e in pairs(cache) do
        table.insert(keys, { nm = nm, t = e.t })
    end
    table.sort(keys, function(a, b) return a.t < b.t end)
    for i = 1, math.floor(#keys / 2) do
        cache[keys[i].nm] = nil
    end
end
local function getWithStat(nm)
    req = req + 1
    local e = get(nm)
    if e ~= nil then hit = hit + 1 end
    return e
end