我的客户有一个图像共享网站，每天大约有 100,000 名访问者，从今天早上我检查进程时发现，它的运行速度已经明显变慢了，http 的 CPU 使用率很高……
顶部
top - 20:13:30 up 5:04, 4 users, load average: 4.56, 4.69, 4.59
Tasks: 284 total, 3 running, 281 sleeping, 0 stopped, 0 zombie
Cpu(s): 12.1%us, 0.9%sy, 1.7%ni, 69.0%id, 16.4%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 16037152k total, 15875096k used, 162056k free, 360468k buffers
Swap: 4194288k total, 888k used, 4193400k free, 14050008k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4151 apache 20 0 277m 84m 3784 R 50.2 0.5 0:01.98 httpd
4115 apache 20 0 210m 16m 4480 S 18.3 0.1 0:00.60 httpd
12885 root 39 19 4296 692 308 S 13.0 0.0 11:09.53 gzip
4177 apache 20 0 214m 20m 3700 R 12.3 0.1 0:00.37 httpd
2219 mysql 20 0 4257m 198m 5668 S 11.0 1.3 42:49.70 mysqld
3691 apache 20 0 206m 14m 6416 S 1.7 0.1 0:03.38 httpd
3934 apache 20 0 211m 17m 4836 S 1.0 0.1 0:03.61 httpd
4098 apache 20 0 209m 17m 3912 S 1.0 0.1 0:04.17 httpd
4116 apache 20 0 211m 17m 4476 S 1.0 0.1 0:00.43 httpd
3867 apache 20 0 217m 23m 4672 S 0.7 0.1 1:03.87 httpd
4146 apache 20 0 209m 15m 3628 S 0.7 0.1 0:00.02 httpd
4149 apache 20 0 209m 15m 3616 S 0.7 0.1 0:00.02 httpd
12884 root 39 19 22336 2356 944 D 0.7 0.0 0:19.21 tar
4054 apache 20 0 206m 12m 4576 S 0.3 0.1 0:00.32 httpd
另一顶
top - 15:46:45 up 5:08, 4 users, load average: 5.02, 4.81, 4.64
Tasks: 288 total, 6 running, 281 sleeping, 0 stopped, 1 zombie
Cpu(s): 18.4%us, 0.9%sy, 2.3%ni, 56.5%id, 21.8%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 16037152k total, 15792196k used, 244956k free, 360924k buffers
Swap: 4194288k total, 888k used, 4193400k free, 13983368k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4622 apache 20 0 209m 16m 3868 S 54.2 0.1 0:03.99 httpd
4514 apache 20 0 213m 20m 3924 R 50.8 0.1 0:04.93 httpd
4627 apache 20 0 221m 27m 4560 R 18.9 0.2 0:01.20 httpd
12885 root 39 19 4296 692 308 S 18.9 0.0 11:51.79 gzip
2219 mysql 20 0 4257m 199m 5668 S 18.3 1.3 43:19.04 mysqld
4512 apache 20 0 227m 33m 4736 R 5.6 0.2 0:01.93 httpd
4520 apache 20 0 213m 19m 4640 S 1.3 0.1 0:01.48 httpd
4590 apache 20 0 212m 19m 3932 S 1.3 0.1 0:00.06 httpd
4573 apache 20 0 210m 16m 3556 R 1.0 0.1 0:00.03 httpd
4562 root 20 0 15164 1388 952 R 0.7 0.0 0:00.08 top
98 root 20 0 0 0 0 S 0.3 0.0 0:04.89 kswapd0
100 root 39 19 0 0 0 S 0.3 0.0 0:02.85 khugepaged
4579 apache 20 0 209m 16m 3900 S 0.3 0.1 0:00.83 httpd
4637 apache 20 0 209m 15m 3668 S 0.3 0.1 0:00.03 httpd
辅助
[root@server ~]# ps aux | grep httpd
root 2236 0.0 0.0 207524 10124 ? Ss 15:09 0:03 /usr/sbin/http d -k start -DSSL
apache 3087 2.7 0.1 226968 28232 ? S 20:04 0:06 /usr/sbin/http d -k start -DSSL
apache 3170 2.6 0.1 221296 22292 ? R 20:05 0:05 /usr/sbin/http d -k start -DSSL
apache 3171 9.0 0.1 225044 26768 ? R 20:05 0:17 /usr/sbin/http d -k start -DSSL
apache 3188 1.5 0.1 223644 24724 ? S 20:05 0:03 /usr/sbin/http d -k start -DSSL
apache 3197 2.3 0.1 215908 17520 ? S 20:05 0:04 /usr/sbin/http d -k start -DSSL
apache 3198 1.1 0.0 211700 13000 ? S 20:05 0:02 /usr/sbin/http d -k start -DSSL
apache 3272 2.4 0.1 219960 21540 ? S 20:06 0:03 /usr/sbin/http d -k start -DSSL
apache 3273 2.0 0.0 211600 12804 ? S 20:06 0:03 /usr/sbin/http d -k start -DSSL
apache 3279 3.7 0.1 229024 29900 ? S 20:06 0:05 /usr/sbin/http d -k start -DSSL
apache 3280 1.2 0.0 0 0 ? Z 20:06 0:01 [httpd] <defun ct>
apache 3285 2.9 0.1 218532 21604 ? S 20:06 0:04 /usr/sbin/http d -k start -DSSL
apache 3287 30.5 0.4 265084 65948 ? R 20:06 0:43 /usr/sbin/http d -k start -DSSL
apache 3297 1.9 0.1 216068 17332 ? S 20:06 0:02 /usr/sbin/http d -k start -DSSL
apache 3342 2.7 0.1 216716 17828 ? S 20:06 0:03 /usr/sbin/http d -k start -DSSL
apache 3356 1.6 0.1 217244 18296 ? S 20:07 0:01 /usr/sbin/http d -k start -DSSL
apache 3365 6.4 0.1 226044 27428 ? S 20:07 0:06 /usr/sbin/http d -k start -DSSL
apache 3396 0.0 0.1 213844 16120 ? S 20:07 0:00 /usr/sbin/http d -k start -DSSL
apache 3399 5.8 0.1 215664 16772 ? S 20:07 0:05 /usr/sbin/http d -k start -DSSL
apache 3422 0.7 0.1 214860 17380 ? S 20:07 0:00 /usr/sbin/http d -k start -DSSL
apache 3435 3.3 0.1 216220 17460 ? S 20:07 0:02 /usr/sbin/http d -k start -DSSL
apache 3463 0.1 0.0 212732 15076 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3492 0.0 0.0 207660 7552 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3493 1.4 0.1 218092 19188 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3500 1.9 0.1 224204 26100 ? R 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3501 1.7 0.1 216916 17916 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3502 0.0 0.0 207796 7732 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3505 0.0 0.0 207660 7548 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3529 0.0 0.0 207660 7524 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3531 4.0 0.1 216180 17280 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3532 0.0 0.0 207656 7464 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3543 1.4 0.1 217088 18648 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3544 0.0 0.0 207656 7548 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3545 0.0 0.0 207656 7560 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3546 0.0 0.0 207660 7540 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3547 0.0 0.0 207660 7544 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3548 2.3 0.1 216904 17888 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3550 0.0 0.0 207660 7540 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3551 0.0 0.0 207660 7536 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3552 0.2 0.0 214104 15972 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3553 6.5 0.1 216740 17712 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3554 6.3 0.1 216156 17260 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3555 0.0 0.0 207796 7716 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3556 1.8 0.0 211588 12580 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3557 0.0 0.0 207660 7544 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3565 0.0 0.0 207660 7520 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3570 0.0 0.0 207660 7516 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
apache 3571 0.0 0.0 207660 7504 ? S 20:08 0:00 /usr/sbin/http d -k start -DSSL
root 3577 0.0 0.0 103316 860 pts/2 S+ 20:08 0:00 grep httpd
httpd 错误日志
[Mon Jul 01 18:53:38 2013] [error] [client 2.178.12.67] request failed: error reading the headers, referer: http://akstube.com/image/show/27023/%D9%86%DB%8C%D9%88%D8%B4%D8%A7-%D8%B6%DB%8C%D8%BA%D9%85%DB%8C-%D9%88-%D8%AE%D9%88%D8%A7%D9%87%D8%B1-%D9%88-%D9%87%D9%85%D8%B3%D8%B1%D8%B4
[Mon Jul 01 18:55:33 2013] [error] [client 91.229.215.240] request failed: error reading the headers, referer: http://akstube.com/image/show/44924
[Mon Jul 01 18:57:02 2013] [error] [client 2.178.12.67] Invalid method in request
[Mon Jul 01 18:57:02 2013] [error] [client 2.178.12.67] File does not exist: /var/www/html/501.shtml
[Mon Jul 01 19:21:36 2013] [error] [client 127.0.0.1] client denied by server configuration: /var/www/html/server-status
[Mon Jul 01 19:21:36 2013] [error] [client 127.0.0.1] File does not exist: /var/www/html/403.shtml
[Mon Jul 01 19:23:57 2013] [error] [client 151.242.14.31] request failed: error reading the headers
[Mon Jul 01 19:37:16 2013] [error] [client 2.190.16.65] request failed: error reading the headers
[Mon Jul 01 19:56:00 2013] [error] [client 151.242.14.31] request failed: error reading the headers
Not a JPEG file: starts with 0x89 0x50
消息日志中也有很多这样的内容
Jul 1 20:15:47 server named[2426]: client 203.88.6.9#11926: query (cache) 'www.xxxmaza.com/A/IN' denied
Jul 1 20:15:47 server named[2426]: client 203.88.6.9#26255: query (cache) 'www.xxxmaza.com/A/IN' denied
Jul 1 20:15:48 server named[2426]: client 203.88.6.9#20093: query (cache) 'www.xxxmaza.com/A/IN' denied
Jul 1 20:15:48 server named[2426]: client 203.88.6.9#8672: query (cache) 'www.xxxmaza.com/A/IN' denied
Jul 1 15:45:07 server named[2426]: client 203.88.6.9#39352: query (cache) 'www.xxxmaza.com/A/IN' denied
系统信息它是一台配备 8 个 Cor 图像的 Xeon CPU 专用服务器，这些图像保存在服务器上
Processor Name Intel(R) Xeon(R) CPU E3-1270 V2 @ 3.50GHz
Vendor ID GenuineIntel
Processor Speed (MHz) 3492.087
Total Memory 16037152 kB
Free Memory 316004 kB
Total Swap Memory 4194288 kB
Free Swap Memory 4193400 kB
System Uptime 0 Days, 6 Hours and 8 Minutes
Apache 2.2.24 Running
DirectAdmin 1.43.0 Running
Exim 4.76 Running
MySQL 5.5.27 Running
Named 9.7.0 Running
ProFTPd 1.3.4b Running
sshd Running
dovecot 2.1.16 Running
Php 5.3.24 Installed
自由的
[root@server ~]# free
total used free shared buffers cached
Mem: 16037152 15686080 351072 0 373364 14132296
-/+ buffers/cache: 1180420 14856732
Swap: 4194288 888 4193400
我的服务器支持人员说这是一次 DDoS 攻击，他们给我发了这张图片，但他们以前也犯过错，所以我担心可能是别的原因
================================
顶部 + 1
top - 20:35:22 up 9:57, 2 users, load average: 4.21, 4.08, 4.14
Tasks: 269 total, 2 running, 267 sleeping, 0 stopped, 0 zombie
Cpu0 : 87.3%us, 3.0%sy, 0.0%ni, 0.0%id, 9.7%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu1 : 12.4%us, 1.0%sy, 1.7%ni, 31.2%id, 53.7%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu2 : 36.1%us, 1.0%sy, 0.0%ni, 20.4%id, 42.5%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu3 : 9.3%us, 0.3%sy, 0.3%ni, 50.0%id, 40.0%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu4 : 0.3%us, 0.0%sy, 0.0%ni, 90.0%id, 9.7%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu5 : 0.3%us, 0.0%sy, 0.7%ni, 93.7%id, 5.3%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu6 : 1.0%us, 0.0%sy, 0.0%ni, 93.3%id, 5.7%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu7 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 16037152k total, 15786500k used, 250652k free, 384284k buffers
Swap: 4194288k total, 932k used, 4193356k free, 14208212k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
40988 apache 20 0 216m 22m 3828 R 89.1 0.1 0:02.70 httpd
2219 mysql 20 0 4257m 207m 5672 S 19.6 1.3 77:18.24 mysqld
23115 root 39 19 4296 692 308 D 5.0 0.0 15:32.00 gzip
40984 apache 20 0 209m 16m 4024 S 1.3 0.1 0:00.09 httpd
41006 apache 20 0 206m 12m 4476 D 1.3 0.1 0:00.80 httpd
另一个
[root@server ~]# top
top - 20:31:55 up 9:53, 2 users, load average: 3.85, 4.04, 4.16
Tasks: 258 total, 2 running, 256 sleeping, 0 stopped, 0 zombie
Cpu0 : 42.5%us, 0.7%sy, 0.0%ni, 2.7%id, 54.2%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu1 : 6.7%us, 1.0%sy, 3.7%ni, 56.5%id, 32.1%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu2 : 5.6%us, 0.3%sy, 0.7%ni, 72.4%id, 20.9%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu3 : 5.3%us, 0.0%sy, 0.3%ni, 85.4%id, 9.0%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu4 : 10.6%us, 0.7%sy, 0.0%ni, 51.7%id, 37.1%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu5 : 0.7%us, 0.3%sy, 0.3%ni, 98.3%id, 0.3%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu6 : 0.0%us, 0.0%sy, 0.0%ni, 94.7%id, 5.3%wa, 0.0%hi, 0.0%si, 0.0%st
Cpu7 : 0.0%us, 0.0%sy, 0.0%ni, 99.3%id, 0.7%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 16037152k total, 15858928k used, 178224k free, 384208k buffers
Swap: 4194288k total, 932k used, 4193356k free, 14347484k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
40654 apache 20 0 260m 66m 4540 R 52.5 0.4 0:04.21 httpd
40512 apache 20 0 217m 23m 4692 D 9.3 0.1 0:04.43 httpd
2219 mysql 20 0 4257m 213m 5672 S 7.0 1.4 76:59.89 mysqld
40638 apache 20 0 208m 16m 3988 S 4.7 0.1 0:00.37 httpd
23115 root 39 19 4296 692 308 S 4.3 0.0 15:22.57 gzip
23114 root 39 19 26436 7768 944 D 0.7 0.0 0:30.64 tar
答案1
我不是网站管理员，也不知道发生了什么
那么，在这里提问可能并不是成为一名网站管理员的正确起点？
如果您对这些事情不太了解，运行自己的名称服务器可能不是一个好主意。
您的 Web 服务器错误处理配置错误。它还在每个实例中使用了相当多的内存。您没有提供任何有关系统内存量的信息（我们需要查看“free”的输出）。
您没有提供任何有关运行该程序的硬件的详细信息（特别是它有多少个 CPU，是物理服务器还是虚拟服务器。也没有提供如何提供图像/使用了多少带宽。
203.88.23.* 网络与您的名称服务器有何关系？
为什么在系统负载很重的时候要以“root”身份运行备份？
实际上，我认为 CPU 使用率并没有那么高，尽管负载和等待时间都相对较高。
我建议你通过调整 Apache 实例的基础知识，使用 noatime 重新挂载包含内容和 MySQL 数据库的磁盘。
答案2
想法 1：Apache 已启用反向 DNS 检查
想法 2：过多的 I/O 导致大量等待