View system resources and load, and performance monitoring under Linux

1, view disk  df-h 2, view memory size  free free [-m|g] Press MB,GB to display memory  vmstat 3, view cpu cat/proc/ cpuinfo  only look at the number of CPUs grep "model name"/proc/cpuinfo | Wc-l 4, view the system memory  cat/proc/meminfo 5, see the situation of each process  cat/proc/5346/status 5347 is pid 6, view load  w  uptime 7, view the overall status of the system  top  explanation of some final output information:  load average:0.09, 0.05, 0.01  The three numbers represent the average system load for different time periods (one minute, five minutes, and 15 minutes), and the number of them is, of course, the smaller the better. "How many cores are the number of loads" rule: in multicore processing, your system should not be higher than the total number of processor cores   the memory used by the process can be used top, there are 3 columns Virt RES SHR, indicating the memory situation used by the process, Virt identifies the total amount of memory that the process can use, including the memory that the process is using, mapped files, and other processes that share memory. Res identifies the size of this process that really consumes memory. The SHR identifies the memory and library sizes that can be shared with other processes.  8, the Performance monitoring SAR command  sar-u output displays CPU information. The-u option is the default option for SAR. The output shows the CPU usage in percent  CPU CPU number  %user  time spent running processes in user mode  %nice  the time it takes to run a normal process  %system   Time spent running a process in kernel mode (System)  %iowait  when no process is executing on that CPU, the time the processor waits for I/O to finish  %idle  when no process is executing on that CPU   SAR 5 SAR obtains 10 samples at 5 second intervals  sar-u-P all 5 5 minutes Cup display  sar-n {DEV | Edev | NFS | NFSD | SOCK | ALL} sar provides six different syntax options to display network information. The-N option uses 6 different switches: DEV | Edev | NFS | NFSD | SOCK | All. The dev Displays the network interface information, Edev displays statistics about network errors, NFS Statistics active NFS Client information, NFSD statistics Server for NFS, sock displays socket information, all shows all 5 switches. They can be used alone or together.  sar-n DEV each parameter means  iface lan interface  rxpck/s  packets received per second  txpck/s  packets sent per second  rxbyt/s   Bytes received per second  txbyt/s  bytes sent per second  rxcmp/s  compressed packets received per second  txcmp/s  packets sent per second   rxmcst/s  Multicast packets received per second  9, view command history (with timestamps)  export histtimeformat= '%F%T '; history| more 10, viewing folder and file size  du-h--max-depth=0 DM View DM directory size  du-h--max-depth=1 DM View DM directory size, and DM file folder size  du-h--max-depth=0 View current folder Size

View system resources and load, and performance monitoring under Linux