/sbin/hdparm -Tt /dev/mpath/36005076304ffd0980000000000005309
/dev/mpath/36005076304ffd0980000000000005309:
Timing cached reads: 24460 MB in 2.00 seconds = 12257.65 MB/sec
Timing buffered disk reads: 326 MB in 3.01 seconds = 108.17 MB/sec
* 注意`hdparm -Tt`只会分析其他进程对block的请求，不会主动产生io；
* 当然是buffered才有分析价值。
rsync -avih /mnt/nfs/memcached-1.2.8-repcached-2.2.1.tar.gz .
>f+++++++++ memcached-1.2.8-repcached-2.2.1.tar.gz
sent 30 bytes received 228.73K bytes 91.50K bytes/sec
total size is 228.58K speedup is 1.00
sudo dd if=/dev/zero of=~/testfile bs=1024 count=10240
10240+0 records in
10240+0 records out
10485760 bytes (10 MB) copied, 0.0591223 s, 177 MB/s
$ sar -b
Linux 4.1.12-gentoo (ins14) 12/30/2015 _x86_64_ (1 CPU)
09:08:22 AM LINUX RESTART (1 CPU)
09:10:01 AM tps rtps wtps bread/s bwrtn/s
09:20:01 AM 15.39 2.18 13.20 109.72 416.11
09:30:01 AM 17.62 4.96 12.66 158.91 394.49
09:40:01 AM 74.08 61.08 13.00 1150.04 475.35
$ sudo iotop -bn1 | head -20
Total DISK READ : 0.00 B/s | Total DISK WRITE : 4.84 M/s
Actual DISK READ: 0.00 B/s | Actual DISK WRITE: 0.00 B/s
TID PRIO USER DISK READ DISK WRITE SWAPIN IO COMMAND
23996 be/4 root 0.00 B/s 4.84 M/s 0.00 % 77.00 % dd if=/dev/zero of=/home/kk/testfile bs=1024 count=10240000
2688 be/4 zabbix 0.00 B/s 0.00 B/s 0.00 % 27.05 % zabbix_server: proxy poller #1 [exchanged data with 0 proxies in 0.003539 sec, idle 5 sec]
1 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % systemd
2 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kthreadd]
3 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [ksoftirqd/0]
5 be/0 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % [kworker/0:0H]