atop
Tools for monitoring Linux system resources and processes
Supplementary instructions
[Non-internal program, installation required] It records the running status of the system at a certain frequency. The collected data includes system resource (CPU, memory, disk and network) usage and process running status, and can be saved in the form of log files. In the disk, after a problem occurs on the server, we can obtain the corresponding atop log file for analysis. atop is an open source software, we can obtain its source code and rpm installation package from here.
grammar
atop(option)(parameter)illustrate
ATOP column: This column displays the host name, information sampling date and time point
PRC column: This column displays the overall running status of the process
CPU column: This column displays the usage of the entire CPU (i.e., multi-core CPU as a whole CPU resource). We know that the CPU can be used to execute processes, handle interrupts, or it can be in an idle state (there are two types of idle states) , one is the active process waiting for disk IO causing the CPU to be idle, the other is completely idle)
The sum of the indication values of each field in the CPU column is N00%, where N is the number of CPU cores.
cpu column: This column displays the usage of a certain core CPU. The meaning of each field can be referred to the CPU column. The sum of the values of each field is 100%.
CPL column: This column displays the CPU load
MEM column: This column indicates memory usage
SWP column: This column indicates swap space usage
PAG column: This column indicates virtual memory paging status
swin, swout fields: number of memory pages swapped in and out
DSK column: This column indicates disk usage. Each disk device corresponds to one column. If there is an sdb device, then an additional column of DSK information is added.
NET column: Multiple NET columns show the network status, including the transport layer (TCP and UDP), IP layer and each active network port information
atop log
The sampling pages at each time point are combined to form an atop log file. We can use the "atop -r XXX" command to view the log file. In what form do you save atop log files?
For how to save atop log files, we can do this:
In fact, atop developers have provided the above log saving methods, and the corresponding atop.daily script can be found in the source code directory. In the atop.daily script, we can change the atop information sampling period by modifying the INTERVAL variable (default is 10 minutes); change the log storage days by modifying the value in the following command (default is 28 days):
(sleep 3; find $LOGPATH -name 'atop_*' -mtime +28 -exec rm {} \; )&Finally, we modify the cron file and execute the atop.daily script every morning:
0 0 * * * root /etc/cron.daily/atop.daily