性能调优

1. CPU Performance Metrics 1.1. CPU Utilization The percentage of non idle time out of total CPU time. Depending on the tasks running on the CPU, it is further divided into user CPU, system CPU, I/O wait CPU, soft interrupts, hard interrupts, etc. Us

1. Memory Performance Metrics 1.1. System Memory Usage 1.1.1. Used Memory Memory that has already been used. 1.1.2. Remaining Memory Memory that has not yet been used. 1.1.3. Shared Memory The amount of memory used by tmpfs; it is also a kind of cach

1. Disk Performance Metrics 1.1. Filesystem I/O Performance Metrics 1.1.1. Storage Space Usage Capacity, used amount, remaining space, etc. 1.1.2. Cache Usage Page cache, directory entry cache, inode cache, and caches for specific filesystems (such a

1. Network Performance Metrics 1.1. Network Layer It is mainly responsible for network packet encapsulation, addressing, routing, sending, and receiving. Performance metric: Number of network packets that can be processed per second, PPS. The kernel'

1. CPU CPU Tuning 2. Memory Memory Tuning 3. Disk Disk Tuning 4. Network Network Tuning

1. perf Command It is a performance analysis tool natively provided by Linux. It returns the function name currently being executed by the CPU and the call stack (stack). 1.1. Usage perf record means record. F 99 means 99 times per second. If all 99