How to troubleshoot high memory usage in Linux?
When the memory usage rate of a Linux system is too high, you can troubleshoot the issue by following these steps:
- Use the command “free -h” to check the system’s memory usage, including total memory, used memory, free memory, and other information.
- Use the top or htop command to check for processes using a lot of memory in the current system. You can sort by memory usage to identify the processes consuming the most memory.
- Use the “ps -eo pid,ppid,cmd,%mem,%cpu –sort=-%mem | head” command to identify the processes using the most memory.
- Use the pmap command to view the memory mapping of a specific process. For example, pmap -d PID can display detailed memory mapping of the specified process.
- Use the vmstat command to view the system’s virtual memory statistics. For example, vmstat -s can be used to check the overall virtual memory usage on the system.
- Check for any instances of memory leaks. You can use the command ps -e -orss=,args= | sort -b -k1,1n | pr -TW$COLUMNS to identify processes that are using a lot of memory and investigate for signs of memory leaks.
- Check for excessive caching or buffer memory usage. You can use the command sync; echo 3 > /proc/sys/vm/drop_caches to clear the cache and buffers, and then monitor the memory usage to see if there is any improvement.
- Check the usage of the system’s swap space. By using the command “free -h”, you can see how the swap space is being utilized. High usage of swap space may result in high memory usage.
- Check the system’s log files to see if there are any errors or warning messages related to memory.
- If the above steps do not solve the issue, you may want to consider upgrading the kernel or reconfiguring the system’s memory management parameters.
Summary: By examining the system’s memory usage, process memory consumption, memory mapping, and other relevant information, along with conducting a comprehensive analysis, one can help troubleshoot the issue of high memory usage in a Linux system.
