lua tcp socket read timed out about lua-resty-mysql HOT 2 OPEN

@rabbate Your code looks good to me though you can save some CPU cycles by putting your main logic into a function in an external Lua module (similar to the resty.mysql module itself).

As long as your nginx worker processes are not blocked by anything, the timeout errors should be something in your mysql server or on the wire in between. It's recommended to always retry 1 or 2 times automatically upon database query failures to take into account such transient timeout errors.

from lua-resty-mysql.

As long as your nginx worker processes are not blocked by anything, the timeout errors should be something in your mysql server or on the wire in between. It's recommended to always retry 1 or 2 times automatically upon database query failures to take into account such transient timeout errors.

@agentzh Are you able to give an example of something like that. I am getting exactly the same error for this code:

local mysql = require "resty.mysql"
local db, err = mysql:new()
if not db then
    ngx.say("failed to instantiate mysql: ", err)
    return
end

db:set_timeout(2000)
-- connect to the database
local ok, err, errorcode, sqlstate = db:connect {
    host = ngx.var.mysql_host,
    port = 3306,
    database = "db",
    user = "root",
    password = "password"
}

if not ok then
    ngx.say("failed to connect: ", err, ": ", errcode, " ", sqlstate)
end


local request_uri = ngx.quote_sql_str(ngx.var.request_uri)
local query = "select target_path from core_url_rewrite where concat('/',request_path)=" .. request_uri .. " AND store_id=" .. ngx.var.store_id

res, err, errcode, sqlstate = db:query(query)

if err then
    ngx.say("Error occured: ", err, errcode, sqlstate)
end

local cjson = require "cjson"
ngx.say(cjson.encode(res))

if res then
    ngx.req.set_uri("/" .. res[1].target_path, true)
    return
end

Error Error occured: failed to receive packet header: timeout

from lua-resty-mysql.