optimize: cache the table for sending requests.

Author: zhuizhuhaomeng

lib/resty/redis.lua

@@ -16,6 +16,7 @@ local tonumber = tonumber
 local tostring = tostring
 local rawget = rawget
 local select = select
+local tb_clear = require "table.clear"
 --local error = error
 
 
@@ -24,7 +25,8 @@ if not ok or type(new_tab) ~= "function" then
  new_tab = function (narr, nrec) return {} end
 end
 
-
+local tab_pool_len = 0
+local tab_pool = new_tab(16, 0)
 local _M = new_tab(0, 55)
 
 _M._VERSION = '0.30'
@@ -59,6 +61,27 @@ local unsub_commands = {
 local mt = { __index = _M }
 
 
+local function get_tab_from_pool()
+ if tab_pool_len > 0 then
+ tab_pool_len = tab_pool_len - 1
+ return tab_pool[tab_pool_len + 1]
+ end
+
+ return new_tab(24, 0) -- one field takes 5 slots
+end
+
+
+local function put_tab_into_pool(tab)
+ if tab_pool_len >= 32 then
+ return
+ end
+
+ tb_clear(tab)
+ tab_pool_len = tab_pool_len + 1
+ tab_pool[tab_pool_len] = tab
+end
+
+
 function _M.new(self)
  local sock, err = tcp()
  if not sock then
@@ -305,9 +328,11 @@ end
 local function _gen_req(args)
  local nargs = #args
 
- local req = new_tab(nargs * 5 + 1, 0)
- req[1] = "*" .. nargs .. "\r\n"
- local nbits = 2
+ local req = get_tab_from_pool()
+ req[1] = "*"
+ req[2] = nargs
+ req[3] = "\r\n"
+ local nbits = 4
 
  for i = 1, nargs do
  local arg = args[i]
@@ -355,6 +380,8 @@ local function _do_cmd(self, ...)
  -- print("request: ", table.concat(req))
 
  local bytes, err = sock:send(req)
+ put_tab_into_pool(req)
+
  if not bytes then
  return nil, err
  end
@@ -625,6 +652,10 @@ function _M.commit_pipeline(self)
  end
 
  local bytes, err = sock:send(reqs)
+ for _, req in ipairs(reqs) do
+ put_tab_into_pool(req)
+ end
+
  if not bytes then
  return nil, err
  end