mysqladmin是MySQL一个重要的客户端，最常见的是使用它来关闭数据库，除此，该命令还可以了解MySQL运行状态、进程信息、进程杀死等。本文介绍一下如何使用mysqladmin extended-status(因为没有"歧义"，所以可以使用ext代替)了解MySQL的运行状态。
1.使用-r/-i参数 使用mysqladmin extended-status命令可以获得所有MySQL性能指标，即show global status的输出，不过，因为多数这些指标都是累计值，如果想了解当前的状态，则需要进行一次差值计算，这就是mysqladmin extended-status的一个额外功能，非常实用。默认的，使用extended-status，看到也是累计值，但是，加上参数-r(–relative)，就可以看到各个指标的差值，配合参数-i(–sleep)就可以指定刷新的频率，那么就有如下命令：
1 2 3 4 5 6 7 8 9 10 mysqladmin -uroot -r -i 1 -pxxx extended-status +------------------------------------------+----------------------+ | Variable_name | Value | +------------------------------------------+----------------------+ | Aborted_clients | 0 | | Com_select | 336 | | Com_insert | 243 | ...... | Threads_created | 0 | +------------------------------------------+----------------------+
2.配合grep使用 配合grep使用，我们就有：
1 2 3 4 5 6 7 8 9 10 11 12 13 mysqladmin -uroot -r -i 1 -pxxx extended-status \ |grep "Questions\|Queries\|Innodb_rows\|Com_select \|Com_insert \|Com_update \|Com_delete " | Com_delete | 1 | | Com_delete_multi | 0 | | Com_insert | 321 | | Com_select | 286 | | Com_update | 63 | | Innodb_rows_deleted | 1 | | Innodb_rows_inserted | 207 | | Innodb_rows_read | 5211 | | Innodb_rows_updated | 65 | | Queries | 2721 | | Questions | 2721 |
3.配合简单的awk使用 使用awk，同时输出时间信息：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 mysqladmin -uroot -p -h127.0.0.1 -P3306 -r -i 1 ext |\ awk -F"|" '{\ if($2 ~ /Variable_name/){\ print " <------------- " strftime("%H:%M:%S") " ------------->";\ }\ if($2 ~ /Questions|Queries|Innodb_rows|Com_select |Com_insert |Com_update |Com_delete |Innodb_buffer_pool_read_requests/)\ print $2 $3;\ }' <------------- 12:38:49 -------------> Com_delete 0 Com_insert 0 Com_select 0 Com_update 0 Innodb_buffer_pool_read_requests 589 Innodb_rows_deleted 0 Innodb_rows_inserted 2 Innodb_rows_read 50 Innodb_rows_updated 50 Queries 105 Questions 1 <------------- 12:38:50 -------------> Com_delete 0 Com_insert 0 Com_select 0 Com_update 0 Innodb_buffer_pool_read_requests 1814 Innodb_rows_deleted 0 Innodb_rows_inserted 0 Innodb_rows_read 8 Innodb_rows_updated 8 Queries 17 Questions 1
4.配合复杂一点的awk 反正也不简单了，那就更复杂一点，这样让输出结果更友好点，因为awk不支持动态变量，所以代码看起来比较复杂：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 mysqladmin -P3306 -uroot -p -h127.0.0.1 -r -i 1 ext |\ awk -F"|" \ "BEGIN{ count=0; }"\ '{ if($2 ~ /Variable_name/ && ++count == 1){\ print "----------|---------|--- MySQL Command Status --|----- Innodb row operation ----|-- Buffer Pool Read --";\ print "---Time---|---QPS---|select insert update delete| read inserted updated deleted| logical physical";\ }\ else if ($2 ~ /Queries/){queries=$3;}\ else if ($2 ~ /Com_select /){com_select=$3;}\ else if ($2 ~ /Com_insert /){com_insert=$3;}\ else if ($2 ~ /Com_update /){com_update=$3;}\ else if ($2 ~ /Com_delete /){com_delete=$3;}\ else if ($2 ~ /Innodb_rows_read/){innodb_rows_read=$3;}\ else if ($2 ~ /Innodb_rows_deleted/){innodb_rows_deleted=$3;}\ else if ($2 ~ /Innodb_rows_inserted/){innodb_rows_inserted=$3;}\ else if ($2 ~ /Innodb_rows_updated/){innodb_rows_updated=$3;}\ else if ($2 ~ /Innodb_buffer_pool_read_requests/){innodb_lor=$3;}\ else if ($2 ~ /Innodb_buffer_pool_reads/){innodb_phr=$3;}\ else if ($2 ~ /Uptime / && count >= 2){\ printf(" %s |%9d",strftime("%H:%M:%S"),queries);\ printf("|%6d %6d %6d %6d",com_select,com_insert,com_update,com_delete);\ printf("|%6d %8d %7d %7d",innodb_rows_read,innodb_rows_inserted,innodb_rows_updated,innodb_rows_deleted);\ printf("|%10d %11d\n",innodb_lor,innodb_phr);\ }}'
1 2 3 4 5 6 7 8 9 10 ----------|---------|--- MySQL Command Status --|----- Innodb row operation ----|-- Buffer Pool Read -- ---Time---|---QPS---|select insert update delete| read inserted updated deleted| logical physical 10:37:13 | 2231| 274 214 70 0| 4811 160 71 0| 4146 0 10:37:14 | 2972| 403 256 84 23| 2509 173 85 23| 4545 0 10:37:15 | 2334| 282 232 66 1| 1266 154 67 1| 3543 0 10:37:15 | 2241| 271 217 66 0| 1160 129 66 0| 2935 0 10:37:17 | 2497| 299 224 97 0| 1141 149 95 0| 3831 0 10:37:18 | 2871| 352 304 74 23| 8202 226 73 23| 6167 0 10:37:19 | 2441| 284 233 82 0| 1099 121 78 0| 3292 0 10:37:20 | 2342| 279 242 61 0| 1083 224 61 0| 3366 0
就这样了，这几个命令自己用的比较多，随手分享出来。
