Linux top process cpu higher than us cpu năm 2024
Whether an application is running on a server or a local machine, monitoring CPU utilization and CPU load is essential for optimizing performance. While CPU utilization and load might sound similar, they’re actually quite different. Show
This article will explain the differences between these two important metrics, how to monitor CPU load with common commands, the impact of high CPU load, and how to bring it under control for improved system performance. CPU utilization versus CPU loadCPU utilization is the percentage of work the CPU is handling to manage tasks. CPU load, on the other hand, is a measurement of how many processes are being executed or waiting to be executed by the CPU. Commands like However, this metric scales with the CPU cores: The more cores installed on the system, the more tasks it can handle in parallel. For example, for a CPU with 4 cores, the accumulated load average will be 4, since each core can handle a load value of 1. In this scenario, even if one of the cores is running at 100% capacity, the CPU would only be loaded with one quarter of its potential load. Now, if the load becomes greater than the number of cores installed, then the processes would start to queue up to use the CPU. Monitoring CPU loadAs noted above, CPU load is averaged over the previous 1, 5, and 15 minute periods. But there are other metrics that also help us identify the CPU load, such as:
Effects of high CPU loadGenerally, a high CPU load doesn't negatively impact a system’s performance, as long as it isn’t a long-term occurrence. But running a CPU at 100% capacity for extended periods can have mild to severe impacts on system performance. A few possible issues are listed below:
Identifying and troubleshooting high CPU loadDifferent commands help monitor the system’s load over different periods. Usually, a smaller number is better, as a higher number indicates an overloaded machine. The next section will cover some of the commands that make it easy to monitor the CPU load averages. Using the top commandThe Running the The first line of this output displays the uptime, the total number of active users logged into the system, and the load averages of the CPU for the last 1, 5, and 15 minute intervals. For example, the above output shows the load averages as 0.13, 0.40, and 0.21. As stated earlier, to properly interpret these numbers, it’s important to know how many cores the CPU has. The above output is from a single-core machine, so the load average is within the acceptable limit, as all of the load averages are less than 1.0. Even if there’s a spike in a 1 and 5-minute duration, as long as the load average of the 15-minute duration is within the limit, there shouldn’t be an issue. Using the uptime commandThe uptime command is also useful for viewing the load average of the system. This command displays the current system time, the uptime of the machine, the number of users currently logged into the system, and the load averages for the last 1, 5 and 15-minute durations. Running the The above output is very similar to the first line of the output of the Using the `uptime`0 commandThe `uptime`0 command is a flexible and widely used tool for identifying the processes running in the system and the number of resources they’re using to run. This command can show different outputs according to various options. Running the `uptime`0 command will generate an output like the one shown below: Fig 3: Output of the ps commandThis output displays basic information about the processes running, but it can be customized with options provided by the `uptime`0 command to yield more details. For example, we can view and sort which processes are using the most CPU by running the following command: ps -eo pcpu,pid,user,args | sort -k 1 -r | head -10 This will result in an output like the one shown below: Fig 4: The top 10 most CPU-consuming processesThe `uptime`0 command doesn’t display the load averages of the system, instead, it’s used to troubleshoot the cause and find the processes that are causing the high CPU load. For example, if a process is using 100% of the CPU, the other processes will have to wait for the CPU and the load on the CPU will increase. This command also helps to identify the processes that are being spawned repetitively or are in a zombie state. Fixing high CPU loadBelow are some common fixes to reduce high CPU load:
ConclusionThe CPU load is an important metric that needs to be monitored regularly to ensure that the system is running smoothly. This metric is generally measured in load averages, but there are some other measurements that indicate the amount of load on the CPU. Luckily, there are a number of useful commands that can help identify and monitor the CPU load. The High CPU load can be an indicator of several problems, and there are various common fixes available to reduce the high load and optimize CPU performance. Why does top show more than 100% CPU?htop shows that cpu usage of per core over 100%? Some blogs explain that this is because I'm using a multi-core machine(this is true). If there are 8 (logic) cores, the max value of CPU% is gonna be 800%. CPU% over 100% means that my task is occupying more than one core. What is top CPU 100% in Linux?Why CPU Utilization is over 100% for a Process in top command? The values of CPU usage over 100% for “YYYY” process is not a problem and it is a absolutely expected behavior on multi-core CPU system based on the man page. It means that the process consumes more than 1 CPU (core). How to find which process is causing high CPU usage in Linux?Check CPU Usage with ps Command The ps command is a flexible and widely used tool for identifying the processes running in the system and the number of resources they're using to run. This command can show different outputs according to various options. What is top process CPU usage in Linux?The top command produces a frequently updated list of processes. By default, the processes are ordered by percentage of CPU usage, with only the “top” CPU consumers shown. The top command shows how much processing power and memory are being used, as well as other information about the running processes. |