sar takes the statistics of different aspects of the machine at a definite time interval. Reducing the time interval for collecting the statistics will increase the amount of detailed statistics we have(because we will be having more data about the system). There is no way, other than taking all the metrics and statistics of the machine at a definite time interval. Which means a monitoring system must be able to provide the statistics of the machine for a given time. If we start thinking about system monitoring, then the tool must have each and every data about the system's different aspects and must cover all time intervals. By default in many Linux distribution you will have a file named /etc/cron.d/sysstat. The main thing that we need to understand regarding SAR is that, everything is done using a cron. Semaphore and memory allocation information.SAR (System Activity Reporter) will Give Information about the following things: Otherwise your distribution DVD will be a nice place to look for the package. Yeah but make it sure that you have epel,rpmformge repository enabled for installing. (But yeah dont worry because most of the distribution comes prepacked with sysstat tool ). You can easily download and install it in your machine very easily through YUM. SAR is one of the utility inside sysstat. Which can be checked by listing all rpm's and finding for this utility. The first thing that we need to do is check and confirm whether you have SAR utility installed on the machine. SAR is very much helpful in doing exactly that. The first thing that most of the Linux system administrators do is to recall the same issue when it previously occurred, and If you remember the day of its previous occurrence then you can easily compare the internal system statistics with the current statistics. If suppose you are having an issue with the system currently, Like some of your customers are unable to list some data from the database. System Activity Reporter is an important tool that helps system administrators to get an overview of the server machine with status of different important metrics at different points of time.

Sar command to check cpu utilization