linux memory exhaustion analysis

The operating system level

1. View the overall health equipment

• loadAverage: 1 minute, the CPU core number 5 minutes, 15 minutes cpu load, full load 1 *
• %us: Cpu utilization of user-space program
• %ss: Cpu utilization of system processes
• %id: Idle cpu
• H/shit+h: Display thread information

1. Memory Analysis

• free -g: View the overall memory usage, observe the following several indicators
• A total of how much memory the operating system
• How much memory has been used
• buffer, cachedThere are how much memory is being used
• -/+ buffers/cache: -Represents the system from an application point of view how much memory is used up, +it represents a system from an application point of view how much memory is available
• How much memory the application uses / applications as well as how much memory can be used
• System monitoring tools:sysstat
  • Installation: zypper in sysstat(including iostat, mpstat, sar, sa)
• High IO load judgment basis:
  • svctm > 15s: The average service time each IO operation
    %utilclose 100%: how much time there is one second for IO operations

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Process analysis

1. Ordering process
   ps -aux | sort -k4,4nr | awk '{sum += $1} END {print "sum=", sum}'
sort参数解释：k后面根的数字表示第几列，n表示数字，r表示逆序排列
2. pidstat

• pidstat -d -p {pid}: The sampling process io
• pidstat -u -p {pid}: The sampling process cpu usage
• pidstat -r -p {pid}: Process memory usage for sampling
• jstack -l {pid}: View all the threads of a process, -l express check-locking
• jstat, jmapEtc.

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Performance Testing

• chaosblade: Ali Chaos Tools
• memtester: Memory testing tools
• cpuburn: Cpu test tools

reference

• linux process under which consumes our cache
• The reason grep use "\ d" matches the digital unsuccessful
• linux command --lsof command everything is a file
• Summary xargs command use parameter substitution
• xargs command tutorial Ruan Yifeng