使用所述方法这里测量服务器响应时间，我可以看到time_appconnect，，time_pretransfer和time_starttransfer非常高，但仅仅是通过 HTTPS 访问网站时才如此。
相比之下，连接谷歌的速度非常快。
curl -w "@curl-format.txt" -o /dev/null -s "https://www.google.com"
返回
time_namelookup: 0.014433
time_connect: 0.117187
time_appconnect: 0.374567
time_pretransfer: 0.374779
time_redirect: 0.000000
time_starttransfer: 0.513398
----------
time_total: 0.514880
通过 HTTP 连接到我们的网站也相当快：
curl -w "@curl-format.txt" -o /dev/null -s "http://environmentaldashboard.org"
返回
time_namelookup: 0.004136
time_connect: 0.044469
time_appconnect: 0.000000
time_pretransfer: 0.044554
time_redirect: 0.000000
time_starttransfer: 0.166275
----------
time_total: 0.166404
但通过 HTTPS 连接非常慢的：
curl -w "@curl-format.txt" -o /dev/null -s "https://environmentaldashboard.org"
返回
time_namelookup: 0.005211
time_connect: 0.057697
time_appconnect: 11.931837
time_pretransfer: 11.932075
time_redirect: 0.000000
time_starttransfer: 11.972374
----------
time_total: 12.009711
这怎么可能？据我所知，这个问题是在代码没有任何变化的情况下发生的。我是一个相当新的系统管理员——我可以使用什么工具来调试这个问题？由于这个问题似乎与 SSL 有关，那么问题是否可能实际上出在我们的证书颁发机构（GoDaddy）身上？或者问题更可能是服务器配置错误？
我不确定这是否相关，但这是 environmentaldashboard.org 的（略微缩写的） apache 虚拟主机文件：
<VirtualHost *:443>
ServerName environmentaldashboard.org
ServerAlias www.environmentaldashboard.org
SSLEngine on
SSLCertificateFile /etc/ssl/environmentaldashboard.org/environmentaldashboard.org.crt
SSLCertificateKeyFile /etc/ssl/environmentaldashboard.org/environmentaldashboard.org.key
SSLCACertificateFile /etc/ssl/environmentaldashboard.org/intermediate.crt
ServerAdmin [email protected]
DocumentRoot /var/www/environmentaldashboard.org/
ErrorDocument 404 /404.php
RewriteEngine On
<Directory /var/www/>
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule !.*\.php$ %{REQUEST_FILENAME}.php [QSA,L]
</Directory>
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
<VirtualHost *:80>
ServerName environmentaldashboard.org
ServerAlias www.environmentaldashboard.org
Redirect permanent / https://environmentaldashboard.org/
</VirtualHost>
编辑
grep -Ev '(rv_cron|15min|PHP Warning)' /var/log/apache2/error.log | tail -n10000
返回此：https://pastebin.com/qZ5e5e1n
和
journalctl -xef | grep -Ev '(rv_cron|15min|buildingosd)'
返回此：
top -d 30 | head -n50返回：
top - 19:02:38 up 8:35, 1 user, load average: 1.71, 1.98, 2.08
Tasks: 281 total, 1 running, 280 sleeping, 0 stopped, 0 zombie
%Cpu(s): 27.9 us, 3.8 sy, 0.0 ni, 55.1 id, 6.5 wa, 0.0 hi, 1.6 si, 5.0 st
KiB Mem : 4046472 total, 1300152 free, 1373280 used, 1373040 buff/cache
KiB Swap: 0 total, 0 free, 0 used. 2336100 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
8736 www-data 20 0 386056 22976 12248 S 55.6 0.6 0:06.03 apache2
15772 root 20 0 256696 81752 7072 S 22.2 2.0 1:34.52 buildingosd
14534 root 20 0 279284 104372 7104 S 16.7 2.6 2:04.70 buildingosd
19708 root 20 0 40680 3736 3116 R 16.7 0.1 0:00.05 top
1340 mysql 20 0 1583808 395376 18808 S 5.6 9.8 87:05.74 mysqld
23451 www-data 20 0 384072 20896 12156 S 5.6 0.5 0:18.71 apache2
1 root 20 0 37760 5756 3956 S 0.0 0.1 0:10.64 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kthreadd
3 root 20 0 0 0 0 S 0.0 0.0 0:05.22 ksoftirqd/0
5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:0H
7 root 20 0 0 0 0 S 0.0 0.0 3:30.70 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 0:00.13 migration/0
10 root rt 0 0 0 0 S 0.0 0.0 0:00.76 watchdog/0
11 root rt 0 0 0 0 S 0.0 0.0 0:00.91 watchdog/1
12 root rt 0 0 0 0 S 0.0 0.0 0:00.14 migration/1
13 root 20 0 0 0 0 S 0.0 0.0 1:13.13 ksoftirqd/1
15 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/1:0H
16 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kdevtmpfs
17 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 netns
18 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 perf
19 root 20 0 0 0 0 S 0.0 0.0 0:00.10 khungtaskd
20 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 writeback
21 root 25 5 0 0 0 S 0.0 0.0 0:00.00 ksmd
22 root 39 19 0 0 0 S 0.0 0.0 0:05.73 khugepaged
23 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 crypto
24 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kintegrityd
25 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
26 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kblockd
27 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 ata_sff
28 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 md
29 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 devfreq_wq
34 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kswapd0
35 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 vmstat
36 root 20 0 0 0 0 S 0.0 0.0 0:00.00 fsnotify_mark
37 root 20 0 0 0 0 S 0.0 0.0 0:00.00 ecryptfs-kthrea
53 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kthrotld
54 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 acpi_thermal_pm
55 root 20 0 0 0 0 S 0.0 0.0 0:00.00 vballoon
56 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
57 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
58 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
59 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
top -d 30以下是其更新的一些内容：
答案1
编辑：
我认为这与证书无关，因为原始 openssl 连接最多需要 5 秒钟才能连接，然后很快返回；https://hastebin.com/ejipapehux.rb
$ openssl s_client -connect environmentaldashboard.org:443 -CAfile /etc/ssl/certs/ca-bundle.trust.crt | ts -s "%.S"
depth=0 C = US, ST = Ohio, L = Oberlin, O = Environmental Dashboard, CN = 104.131.103.232
verify error:num=18:self signed certificate
verify return:1
depth=0 C = US, ST = Ohio, L = Oberlin, O = Environmental Dashboard, CN = 104.131.103.232
verify return:1
05.800695 CONNECTED(00000003)
05.800967 ---
05.801019 Certificate chain
05.801060 0 s:/C=US/ST=Ohio/L=Oberlin/O=Environmental Dashboard/CN=104.131.103.232
需要 5 秒或更长时间来响应初始Hello，因此我会检查服务器并查看发生了什么；
您有机器的控制台访问权限吗？