High Memory Usage: Diagnostics & Troubleshooting
When your systems runs out of RAM
High memory usage can occur due to various factors, including resource-intensive processes, memory leaks, or inefficient memory management. Diagnosing and solving high memory usage requires identifying the processes or components responsible and taking appropriate actions.
Here's an overview of the process:
Identifying high memory usage
The free
command provides a summary of memory usage and available memory.
The "used"
column shows the total used memory, and "free"
indicates the available memory.
The top
or htop
commands display real-time information about running
processes, including memory consumption. Look for processes using a significant amount of memory.
The ps
command with memory-related options, such as ps aux --sort=-%mem
, lists processes
sorted by memory usage.
The /proc/meminfo
file contains detailed information about memory usage.
Read values like "MemTotal"
, "MemFree"
, and "Buffers"
to gain insights into memory utilization.
Identifying memory-hungry processes
In top
or htop
, sort processes by memory usage to identify the
top offenders. Look for processes with increasing memory consumption over time, as they may indicate
memory leaks.
Tools for detailed memory analysis
The pmap
command provides a detailed breakdown of memory usage for a specific process.
Running pmap <PID>
displays the memory mappings for the process with the specified PID
.
Solving high memory usage issues
Restart the problematic process or application, especially if it's a one-time occurrence.
Identify and fix memory leaks in software code.
Adjust system configurations, such as reducing swappiness (how often the system swaps memory to disk) or increasing the amount of swap space.
Consider upgrading the system's RAM if memory demands consistently exceed available resources.
Optimize resource-intensive applications by adjusting their configurations or using more efficient alternatives. Especially pay attention to databases such as mariadb or PostgreSQL as they can use a lot of memory. Incorrect configuration may not be a problem at the beginning but show up later when lots of data have been loaded into the database.
Review and optimize system services and daemons that consume excessive memory.
Ensure that your Linux distribution and software packages are up to date, as newer versions often include bug fixes and performance improvements.
Remember that diagnosing and solving high memory usage requires a case-by-case approach, as each situation may have unique causes.
How CleverUptime monitors memory usage
CleverUptime not only monitors overall memory usage such as free RAM, but also memory usage of individual processes.