Linux Common Operations Command

Iostat to monitor IO performance

#iostat-D-K 1 20

Display Throughput Kb_read/s,kb_write/s,tps

Device:tps kb_read/s kb_wrtn/s Kb_read kb_wrtnsda7.00        64.00        24.00          -          -sda10.00         0.00         0.00          0          0sda20.00         0.00         0.00          0          0Sda30.00         0.00         0.00          0          0sda40.00         0.00         0.00          0          0Sda57.00        64.00        24.00          -          -

TPS: The number of times a device transmits per second (a single transmission may contain multiple IO requests);

KB_READ/S: The amount of data read per second, KB_WRTN/S: The amount of data written to the device per second;

Kb_read and Kb_wrtn, respectively, are read and write quantities, in kilobytes.

#iostat-D-k-x 1 20

Show detailed information, mainly see device usage%util and response time await

device:rrqm/s wrqm/s r/sW/s rkb/s wkb/s avgrq-sz Avgqu-sz await SVCTM%UTILSDA0.00     0.00  4.00  0.00    64.00     0.00    32.00     0.02    6.00   6.00   2.40sda10.00     0.00  0.00  0.00     0.00     0.00     0.00     0.00    0.00   0.00   0.00sda20.00     0.00  0.00  0.00     0.00     0.00     0.00     0.00    0.00   0.00   0.00Sda30.00     0.00  0.00  0.00     0.00     0.00     0.00     0.00    0.00   0.00   0.00sda40.00     0.00  0.00  0.00     0.00     0.00     0.00     0.00    0.00   0.00   0.00Sda50.00     0.00  4.00  0.00    64.00     0.00    32.00     0.02    6.00   6.00   2.40

rrqm/s: How many times per second the read operation of the device is merged (when different session operations access the same data on the device at the same time), and the wrqm/s: how many times per second the device's write operation is merge;

RKB/S: The fan block scanned by the read operation per second, wkb/s: the fan block scanned by the write operation per second, the number of read operations per second processed by the r/s, and the number of write operations processed per second w/s

Await: The average time it takes to process an IO operation;

%util: Device IO utilization, calculated by 0.6 seconds for IO operation in 1 seconds, then%util is 60%

#iostat-C 1 20

View CPU Information

AVG-CPU:  %user   % nice%system%iowait  %steal   %idle           0.63     0.00    0.25    0.00    0.00   99.12