什么是监控工具Linux iotop

这期内容当中小编将会给大家带来有关什么是监控工具Linux iotop，文章内容丰富且以专业的角度为大家分析和叙述，阅读完这篇文章希望大家可以有所收获。

iotop的简介：

iotop是一款开源、免费的用来监控磁盘I/O使用状况的类似top命令的工具，iotop可以监控进程的I/O信息。它是Python语言编写的，与iostat工具比较，iostat是系统级别的IO监控，而iotop是进程级别IO监控。目前最新的版本为iotop 0.6。其官方网址http://guichaz.free.fr/iotop/[1]

iotop的安装：

注意，iotop的安装有前提条件(如果操作系统不满足这些条件，iotop无法正确安装)：

1：内核版本为2.6.20或更高版本

2：Python 2.7或更高的版本

官方文档的详细介绍如下：

• Linux has always been able to show how much I/O was going on (the bi and bo columns of the vmstat 1 command).

• Iotop is a Python program with a top like UI used to show of behalf of which process is the I/O going on. It requires Python ≥ 2.7 and a Linux kernel ≥ 2.6.20 with the TASK_DELAY_ACCT CONFIG_TASKSTATS, TASK_IO_ACCOUNTING and CONFIG_VM_EVENT_COUNTERS options on.

iotop的yum安装

yum安装是最简单、快捷的。前提条件是你有配置yum的源配置。

[root@DB-Server ~]# python -V Python 2.7.5 [root@DB-Server ~]# uname -a Linux DB-Server 3.10.0-862.el7.x86_64 #1 SMP Fri Apr 20 16:44:24 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux [root@DB-Server ~]#      [root@DB-Server ~]# yum -y install iotop

iotop的源码安装

wget http://guichaz.free.fr/iotop/files/iotop-0.6.tar.bz2 tar -xvf iotop-0.6.tar.gz  cd iotop-0.6 python setup.py build python setup.py install

iotop的参数

# iotop --help Usage: /usr/local/sbin/iotop [OPTIONS]   DISK READ and DISK WRITE are the block I/O bandwidth used during the sampling period. SWAPIN and IO are the percentages of time the thread spent respectively while swapping in and waiting on I/O more generally. PRIO is the I/O priority at which the thread is running (set using the ionice command).   Controls: left and right arrows to change the sorting column, r to invert the sorting order, o to toggle the --only option, p to toggle the --processes option, a to toggle the --accumulated option, i to change I/O priority, q to quit, any other key to force a refresh.   Options:   --version             show program's version number and exit   -h, --help            show this help message and exit   -o, --only            only show processes or threads actually doing I/O   -b, --batch           non-interactive mode   -n NUM, --iter=NUM    number of iterations before ending [infinite]   -d SEC, --delay=SEC   delay between iterations [1 second]   -p PID, --pid=PID     processes/threads to monitor [all]   -u USER, --user=USER  users to monitor [all]   -P, --processes       only show processes, not all threads   -a, --accumulated     show accumulated I/O instead of bandwidth   -k, --kilobytes       use kilobytes instead of a human friendly unit   -t, --time            add a timestamp on each line (implies --batch)   -q, --quiet           suppress some lines of header (implies --batch)

iotop的快捷键

r：反向排序，

o：切换至选项--only，

p：切换至--processes选项，

a：切换至--accumulated选项

q：退出

i：改变线程的优先级

iotop的例子

1：只显示正在产生I/O的进程

# iotop -o

2：使用非交互模式将iotop命令输出信息写入日志

#nohup iotop -b -o -n 10 -d 5 -t  > /tmp/iotop.log &

3：借助iotop命令找到消耗I/O最高的进程，然后通过进程找到其正在执行的SQL语句

# iotop -oP   PID  PRIO  USER     DISK READ  DISK WRITE  SWAPIN     IO>    COMMAND                                                                                                                       11741 be/4 oracle      4.70 M/s    0.00 B/s  0.00 % 98.60 % ora_s004_SCM2  11739 be/4 oracle     66.99 M/s    0.00 B/s  0.00 % 93.30 % ora_s005_SCM2  11741 be/4 oracle     21.76 M/s    0.00 B/s  0.00 % 91.78 % ora_s006_SCM2  11743 be/4 oracle      4.87 M/s    3.78 M/s  0.00 % 27.74 % ora_s007_SCM2  11745 be/4 oracle     62.39 K/s    0.00 B/s  0.00 %  2.88 % ora_s008_SCM2  11733 be/4 oracle     39.00 K/s    0.00 B/s  0.00 %  2.08 % ora_s002_SCM2                  11697 be/4 oracle      0.00 B/s 1879.61 K/s  0.00 %  0.30 % ora_dbw0_SCM2  11699 be/4 oracle      0.00 B/s  102.36 K/s  0.00 %  0.20 % ora_lgwr_SCM2

在找到消耗I/O最大的进程后，找出ORACLE进程正在执行的SQL语句

SQL> @getsql_by_spid.sql  Enter value for pid: 11741  old  13:                                WHERE c.spid = '&pid'))  new  13:                                WHERE c.spid = '11741'))     SQL_TEXT  --------------------------------------------  ...............................(实际环境中，这里会输出SQL语句)

getsql_by_spid.sql脚本如下所示：

SELECT   /*+ ORDERED */          sql_text     FROM v$sqltext a    WHERE (a.hash_value, a.address) IN (             SELECT DECODE (sql_hash_value,                            0, prev_hash_value,                            sql_hash_value                           ),                    DECODE (sql_hash_value, 0, prev_sql_addr, sql_address)               FROM v$session b              WHERE b.paddr = (SELECT addr                                 FROM v$process c                                WHERE c.spid = '&pid')) ORDER BY piece ASC /

这里只简单列了几个例子，因为iotop命令非常简单，了解iotop的参数和快捷方式后，基本上只需根据实际需求去获取进程或信息的I/O信息，剩下就是分析判断了。

上述就是小编为大家分享的什么是监控工具Linux iotop了，如果刚好有类似的疑惑，不妨参照上述分析进行理解。如果想知道更多相关知识，欢迎关注行业资讯频道。