Why does PDO take 1 second to connect?

Question

I use MySQL Workbench to run queries. It takes literally no time at all to run them. However, when I connect to the database via PDO, it takes over one second to connect! Why?

<?php

$host = "localhost";
$db = "localhost";
$user = "root";
$pass = "";

$mtime = explode(" ",microtime());
$starttime = $mtime[1] + $mtime[0];

$conn = new PDO("mysql:host=$host;dbname=$db",$user,$pass);

$mtime = explode(" ",microtime());
$totaltime = (($mtime[1] + $mtime[0]) - $starttime);
echo $totaltime * 1000;

This outputs:

1008.975982666

Is workbench connecting via `localhost` or `127.0.0.1` or some other name? Connection speed issues are often related to DNS lookup issues. If you have a shell (and this is a Unix-like machine, does `dig localhost` return quickly? `localhost` should be defined as `127.0.0.1` but there could be something weird with the hosts file. — Michael Berkowski, Nov 25 '12 at 21:30
Call `microtime(true)` to get a float value of the current time, and get rid of this whole explode-time-calculation-thingie. — Sven, Nov 25 '12 at 21:30
A database named "localhost" sounds strange to me. Are you sure this is right. — Sven, Nov 25 '12 at 21:31
Maybe because connecting to a database and running queries through an established connection are tasks in different weight categories? — Desmond Hume, Nov 25 '12 at 21:31
@Subash You wouldn't believe me if I told you how many times I've got comments on that! — Student of Hogwarts, Nov 25 '12 at 21:33
@DesmondHume I don't know if MySQL WB has an established connection or not... Got an answer though! — Student of Hogwarts, Nov 25 '12 at 21:33
@studentOfHogwarts I can imagine. Good luck with your question. — Subash, Nov 25 '12 at 21:35
Lesson 0: Never just copy and paste random codes from the interwebs! :P — deceze, Nov 25 '12 at 21:37
@Sven Yes, you are correct. I just named it this because we have not yet decided the name of our project.. Doesn't matter since changing this in one include file is easy :) — Student of Hogwarts, Nov 25 '12 at 21:38

score 9 · Accepted Answer · answered Nov 25 '12 at 21:31

9

On windows vista and newer use 127.0.0.1 instead of localhost.

answered Nov 25 '12 at 21:31

dev-null-dweller

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Great! It worked! Why is that? When I enter http://localhost/, it doesn't take 1 second to load? Is the browser caching the DNS? – Student of Hogwarts Nov 25 '12 at 21:32
1

@StudentofHogwarts: See http://stackoverflow.com/questions/3715925/localhost-vs-127-0-0-1 – Aamir Nov 25 '12 at 21:33
Not really sure, but I remember reading that windows first tries IPv6 address (`:::1`) for localhost and then `127.0.0.1` if it fails. – dev-null-dweller Nov 25 '12 at 21:37

Why does PDO take 1 second to connect?

1 Answers1