Joomla 1.5：如何在基于joomla的Intranet系统中查找并发/活动用户数

Question

I have a Joomla 1.5.10 based Intranet system. Sometimes we see that number of DB threads are too high and performance become down. When I checked through Administrator section, I can see the number of logged-in users only. These number is between 1000-5000 only. is it correct to execute below query to find the concurrent active users:

select count(*) from jos_session;

For example, If I execute above query and check the logged-in user through administrator, below is the data:

select count(*) from jos_session; = 2628
logged-in users visible from admin section = 1545

Both results are not matching each other. Also, what is the best way to find the concurrent / active users in my system at a time?

Answer 1

I think just by analizing __session you won't get the info you need / want. If you need to understand what you see in back-end, check the module located at:

administrator\\modules\\mod_status\\mod_status.php

There are all the queries listed. Important is to understand that guest is an user which is not authenticated, and also client_id (front-end (0) VS backend authentication (1)).

Here is the thing:

• jos_session stores all the sessions that have not expired
• probably you have a SSO authentication mechanism, which means that the user probably get a new session id if it closes and opens again the browser. Having more active sessions than users it's a clear sign that the session expiration time is set to high.

Just do a query against the jos_session :

SELECT `username`, count(username) FROM `jos_session` WHERE 1 GROUP BY `username`

If too many users have a too large value for count , reduce the session lifetime.

This way you will get a more realistic figure on how many users are at a certain time in the system, but again this is just a session, it does not provide you with exact information on how many users are actually performing an action on a website.

To put it in plain English is like saying: I know that 1500 users opened the Intranet in the last [FILL IN SESSION LIFETIME] minutes.

You need to understand how exactly do the DB threads get generated and why the value is high.

Basically, quoting the documentation , The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling mysql_close().

Might be worth checking if you have something like a JavaScript polling your server with AJAX requests to get some info, which might run even if the user just has the browser open.

Hope this helps in a way or another.