aix iostat disk performance

"style=" border:0px;vertical-align:middle;margin:5px 20px 20px 0px;height:auto; "/>Conclusion:It is found that the disk reads and writes are high, and the SVCTM and await are very different.The value of 1,await is much higher than the value of SVCTM, which means that the I/O queue waits too long for the applications running on the system to become slower.The value of the 2,%util key is also an important metric for measuring

Case phenomenon:When the pressure test, found a request pressure 80tps, the CPU occupied is very high (24-core machine, each CPU occupation rate of the total soared to more than 80%), and set the checkpoint did not have any error.1. The top command is as follows:2, understand the background to implement the logic: The general is such: after the server received the request, will be another KV server request data, take back the data, according to the user's machine code to do personalized operatio

milliseconds) per device I/O operation. Delta (use)/delta (RIO+WIO) %util: CPU usage time per second for IO operations. That is, the amount of time in a second for I/O operations, or how much time in a second I/O queue is non-empty, calculation method: (r/s+w/s) * (svctm/1000) %util indicates how busy the disk is. 100% indicates that the disk is busy and 0% indicates that the

] [-t] [-X [Device]] [interval [count]]-C: Show CPU usage-D: Show disk usage-K: Display data in K bytes per second-T: Print out the time when statistics start executing-X Device: Specifies the disk device name to be counted, which defaults to all disk devicesInterval: Two time intervals for statisticsCount: Number of statisticssuch as:

Test disk IO speed with time+dd+ifWrite Speed:Time DD If=/dev/zero of=test.dbf bs=8k count=300000Where/dev/zero is a pseudo-device that produces only a stream of empty characters and does not produce IO for it, so the IO is concentrated in the of file, the of file is used only for writing, so this command is equivalent to the write capability of the test disk.The output is similar (because generally longer test times are more accurate, so you can set

the execution times of the two command lines.(4) The parenthesis means that another child process to execute the script in parentheses, DD This command line here does not say, do not know Baidu bar.The focus is on the sync command, because when DD exits, most of the content that this command line commits is in memory buffers (write cache), even if the machine's memory is much larger than the data you submit,It is possible that the data is in memory, and then the sync is performed to write the m

Disks are usually the slowest subsystem of the computer and are the most prone to performance bottlenecks because the disk is farthest from the CPU and the CPU accesses the disk to involve mechanical operations such as rotating shafts, track-seeking, etc. The speed difference between accessing the hard disk and accessi

Tags: Linux grab tcpdump netstat view network status PS System State free memory usage Iostat disk performanceMonitoring IO Disk Performance命令如下：iostat -x 磁盘使用iotop 磁盘使用 %util look at the health of a hard drive, Installing Iotop[[emailprotected] ~]# yum install