Monitoring a MySQL Server Process

• Download MySQLserverMonitor - 2.82 MB

Introduction

This article is an example of monitoring a process. It will look for a running process and can start and stop the process, too.

Background

If you are using MySQL 5 as a database server, you already know that there are no icons that show whether the server is running or not. You can look at the task manager, but perhaps you want to shutdown the server because the development session is over and the server uses so much memory (about 50 MB). If you installed the server as a service, you can stop the service, but you must have administrator privileges. If MySQL is not run as a service, you can execute a program to start and stop the server and this article contains the code to easily do that.

Using the code

To use this code, you need the MySQL server software that can be downloaded from www.mysql.com[^], but in reality, any software will do. This just an example.

The program works by monitoring the existence of a running process that you can check with the Windows Task Manager.

As shown in the figure, the MySQL server process is named mysqld.exe. To monitor the process, this code is executed periodically with a Timer event as follows:

private void timer1_Tick(object sender, EventArgs e)
{
    Process[] server =  Process.GetProcessesByName("mysqld");            
    if (server.Length != 0)
    {
        bool stat = true;
        //check if current status same as previous. this prevent notification always shown
        if (serverStat != stat) 
        {
            OnRaiseServerEvent(new serverEventArgs(true)); //raise server event
            serverStat = stat;
        }                
    }
    else
    {
        bool stat = false ;
        //check if current status same as previous. this prevent notification always shown
        if (serverStat != stat) 
        {
            OnRaiseServerEvent(new serverEventArgs(false)); //raise server event
            serverStat = stat; //update global status
        }                         
    }
}

Starting the server is easy; just execute mysqld.exe and it's done. Unfortunately you can't simply stop the process to shutdown the server. Well, it could be done, but an internal error might occur inside the server. To stop the server, you should instead execute: mysqladmin.exe --user=root shutdown.

To start the server:

FileInfo fi = new FileInfo(appPath + "\\mysqld.exe");
if (fi.Exists)
    Process.Start(fi.FullName);
else
    errorProvider1.SetError(txtPath, "this isn't mysql installation directory");

Similarly, to stop the server:

FileInfo fi = new FileInfo (appPath + "\\mysqladmin.exe");
if (fi.Exists)
    Process.Start(fi.FullName, "--user=root shutdown");
else
    errorProvider1.SetError(txtPath, "this isn't mysql installation directory");

Points of Interest

This code is useful if you are running MySQL server. You can start and stop the server by clicking a button, rather than by typing from a command prompt. You can also click on a button installed in the system tray as shown in the following image.