使用SAR分析磁盘IO性能

Question

本帖最后由 cu_Cbear 于 2011-05-03 20:05 编辑

使用SAR分析磁盘IO性能



# sar -d 5 10

单位 sector=512B = 0.5KB

tps
每秒IO次数
Indicate  the number of transfers per second that were issued to the device.
Multiple logical requests can be combined into a single I/O request to the device.
A transfer is of indeterminate size

rd_sec/s
每秒读取的sector数
Number of sectors read from the device

wr_sec/s
每秒写入的sector数
Number of sectors written to the device

avgrp-sz
流出设备的扇区数
The average size (in sectors) of the requests that were issued to the device.

avgqu-sz
流出设备的平均队列长度, 每秒平均请求数
The average queue length of the requests that were issued to the device.

await
平均请求与服务时间(in milliseconds毫秒)
The average time (in milliseconds) for I/O requests issued to the device to be served.
This includes the time spent by the requests in queue and the time  spent servicing them.

svctm
平均服务时间(in millisecods)
The average service time (in milliseconds) for I/O requests that were issued to the device.

%util
IO平均的CPU使用时间, 数字接近100%时，设备出现饱和
Percentage  of  CPU time during which I/O requests were issued to the device (bandwidth utilization for the device).
Device saturation occurs when this value is close to 100%.

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2011-05-03 20:04 上传

定位是/dev/sda6这块磁盘IO压力比较大

  

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你还可以用iostat 查看相关信息：
# iostat -x 1 5

Answer 1

sar 是好东西，今天回过来再看一下sar常用命令：

查看cpu:

sar -u

查看I/O:

sar -b

查看内存使用情况:

sar -r

查看网卡流量统计:

sar -n EDEV