我经营一个小型视频流网站，我注意到我的网站上的视频存在一些问题。
顶部
top - 15:43:48 up 34 days, 1:22, 1 user, load average: 37.80, 38.08, 38.38
Tasks: 184 total, 1 running, 183 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.5 us, 0.5 sy, 0.0 ni, 6.0 id, 85.1 wa, 0.0 hi, 7.8 si, 0.0 st
KiB Mem : 32730324 total, 1575916 free, 1470200 used, 29684208 buff/cache
KiB Swap: 33313788 total, 33308768 free, 5020 used. 30448240 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
3 root 20 0 0 0 0 S 16.9 0.0 5554:20 ksoftirqd/0
2827 www-data 20 0 398696 84756 5548 S 6.0 0.3 213:14.78 nginx
2828 www-data 20 0 324716 10900 5548 S 1.7 0.0 14:46.99 nginx
40 root 20 0 0 0 0 S 0.3 0.0 148:03.47 ksoftirqd/5
198 root 0 -20 0 0 0 S 0.3 0.0 11:16.66 kworker/0:+
1086 root 20 0 44044 3668 2988 R 0.3 0.0 0:00.21 top
2829 www-data 20 0 319180 6660 5396 S 0.3 0.0 1:51.37 nginx
27962 root 20 0 109956 9704 7836 S 0.3 0.0 0:00.53 exim4
1 root 20 0 204648 5072 3644 S 0.0 0.0 1:47.36 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.16 kthreadd
5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+
7 root 20 0 0 0 0 S 0.0 0.0 31:06.23 rcu_sched
8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh
9 root rt 0 0 0 0 S 0.0 0.0 0:01.11 migration/0
10 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 lru-add-dr+
11 root rt 0 0 0 0 S 0.0 0.0 1:16.83 watchdog/0
12 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/0
艾拓普
Total DISK READ : 59.96 M/s | Total DISK WRITE : 0.00 B/s
Actual DISK READ: 59.96 M/s | Actual DISK WRITE: 8.84 K/s
TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
2902 be/4 www-data 377.17 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2845 be/4 www-data 1508.66 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2864 be/4 www-data 754.33 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2832 be/4 www-data 1005.78 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2888 be/4 www-data 754.33 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2883 be/4 www-data 848.62 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2836 be/4 www-data 1382.94 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2849 be/4 www-data 628.61 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2841 be/4 www-data 660.04 K/s 0.00 B/s 0.00 % 99.58 % nginx: wo~er process
2853 be/4 www-data 880.05 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2831 be/4 www-data 754.33 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2859 be/4 www-data 1382.94 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2835 be/4 www-data 1005.78 K/s 0.00 B/s 0.00 % 99.87 % nginx: wo~er process
2851 be/4 www-data 628.61 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2834 be/4 www-data 754.33 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2839 be/4 www-data 880.05 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2860 be/4 www-data 251.44 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2892 be/4 www-data 628.61 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2843 be/4 www-data 880.05 K/s 0.00 B/s 0.00 % 99.99 % nginx: wo~er process
2833 be/4 www-data 377.17 K/s 0.00 B/s 0.00 % 99.97 % nginx: wo~er process
2856 be/4 www-data 754.33 K/s 0.00 B/s 0.00 % 99.97 % nginx: wo~er process
当我停止我的网站并尝试运行磁盘速度时，这就是我所得到的。
# dd if=/dev/zero of=tempfile bs=10M count=1024 conv=fdatasync,notrunc status=progress
10622074880 bytes (11 GB, 9.9 GiB) copied, 46.0385 s, 231 MB/s
1024+0 records in
1024+0 records out
10737418240 bytes (11 GB, 10 GiB) copied, 92.1228 s, 117 MB/s
那么，目前我可以推高到 120 MB/s 并且 iotop 报告我达到了 60 MB/s，为什么如果我只使用半速就会出现高负载 IO 问题？
我该如何调整或解决这个问题？我正在使用 nginx 来提供 mp4 视频。