⚝
One Hat Cyber Team
⚝
Your IP:
216.73.216.23
Server IP:
178.33.27.10
Server:
Linux cpanel.dev-unit.com 3.10.0-1160.108.1.el7.x86_64 #1 SMP Thu Jan 25 16:17:31 UTC 2024 x86_64
Server Software:
Apache/2.4.57 (Unix) OpenSSL/1.0.2k-fips
PHP Version:
8.2.11
Buat File
|
Buat Folder
Eksekusi
Dir :
~
/
usr
/
local
/
src
/
netdata
/
health
/
guides
/
load
/
View File Name :
load_average_1.md
### Understand the alert This alarm calculates the system `load average` (`CPU` and `I/O` demand) over the period of one minute. If you receive this alarm, it means that your system is `overloaded`. ### What does "load average" mean? The term `system load average` on a Linux machine, measures the **number of threads that are currently working and those waiting to work** (CPU, disk, uninterruptible locks). So simply stated: **System load average measures the number of threads that aren't idle.** ### What does "overloaded" mean? Let's look at a single core CPU system and think of its core count as car lanes on a bridge. A car represents a process in this example: - On a 0.5 load average, the traffic on the bridge is fine, it is at 50% of its capacity. - If the load average is at 1, then the bridge is full, and it is utilized 100%. - If the load average gets to 2 (remember we are on a single core machine), it means that there is one car lane that is passing the bridge. However, there is **another** full car lane that waits to pass the bridge. So this is how you can imagine CPU load, but keep in mind that `load average` counts also I/O demand, so there is an analogous example there. ### Troubleshoot the alert - Determine if the problem is CPU load or I/O load To get a report about your system statistics, use `vmstat` (or `vmstat 1`, to set a delay between updates in seconds): The `procs` column, shows: r: The number of runnable processes (running or waiting for run time). b: The number of processes blocked waiting for I/O to complete. - Check per-process CPU/disk usage to find the top consumers 1. To see the processes that are the main CPU consumers, use the task manager program `top` like this: ``` top -o +%CPU -i ``` 2. Use `iotop`: `iotop` is a useful tool, similar to `top`, used to monitor Disk I/O usage, if you don't have it, then [install it](https://www.tecmint.com/iotop-monitor-linux-disk-io-activity-per-process/) ``` sudo iotop ``` 3. Minimize the load by closing any unnecessary main consumer processes. We strongly advise you to double-check if the process you want to close is necessary. ### Useful resources 1. [UNIX Load Average Part 1: How It Works](https://www.helpsystems.com/resources/guides/unix-load-average-part-1-how-it-works) 2. [UNIX Load Average Part 2: Not Your Average Average](https://www.helpsystems.com/resources/guides/unix-load-average-part-2-not-your-average-average) 3. [Understanding Linux CPU Load](https://scoutapm.com/blog/understanding-load-averages) 4. [Linux Load Averages: Solving the Mystery](https://www.brendangregg.com/blog/2017-08-08/linux-load-averages.html) 5. [Understanding Linux Process States](https://access.redhat.com/sites/default/files/attachments/processstates_20120831.pdf)