我们在 Debian 系统上将内核从 2.6.32 升级到了 3.8.7。我们与 NFS 共享以获取 Apache2 的数据。并且 Nginx 仅作为代理提供静态文件。由于我们安装了内核 3.8.7，因此平均负载有时会增加（达到 40 甚至更多），并且我们发现“/var/log/messages”上写有错误。
这是常见的错误：
Apr 17 06:07:44 node1 kernel: [116569.387483] INFO: task apache2:18604 blocked for more than 120 seconds.
Apr 17 06:07:44 node1 kernel: [116569.387527] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Apr 17 06:07:44 node1 kernel: [116569.387598] apache2 D 0000000000000002 0 18604 17528 0x00000000
Apr 17 06:07:44 node1 kernel: [116569.387602] ffff8802338f1d98 0000000000000082 ffff8802338f0010 0000000000013940
Apr 17 06:07:44 node1 kernel: [116569.387605] ffff880222454a40 0000000000013940 ffff8802338f1fd8 0000000000013940
Apr 17 06:07:44 node1 kernel: [116569.387608] ffff8802338f1fd8 0000000000013940 ffff880236543180 ffff880222454a40
Apr 17 06:07:44 node1 kernel: [116569.387614] Call Trace:
Apr 17 06:07:44 node1 kernel: [116569.387622] [<ffffffff815681de>] schedule+0x64/0x66
Apr 17 06:07:44 node1 kernel: [116569.387625] [<ffffffff81568426>] schedule_preempt_disabled+0xe/0x10
Apr 17 06:07:44 node1 kernel: [116569.387628] [<ffffffff81567178>] __mutex_lock_common+0x11d/0x18b
Apr 17 06:07:44 node1 kernel: [116569.387633] [<ffffffff8113dc17>] ? filename_lookup+0x74/0x84
Apr 17 06:07:44 node1 kernel: [116569.387636] [<ffffffff81567201>] __mutex_lock_slowpath+0x1b/0x1d
Apr 17 06:07:44 node1 kernel: [116569.387639] [<ffffffff81566fbd>] mutex_lock+0x1b/0x2c
Apr 17 06:07:44 node1 kernel: [116569.387642] [<ffffffff8113e75d>] do_unlinkat+0x92/0x231
Apr 17 06:07:44 node1 kernel: [116569.387645] [<ffffffff81131d6e>] ? fsnotify_access+0x5d/0x65
Apr 17 06:07:44 node1 kernel: [116569.387648] [<ffffffff81132f13>] ? sys_read+0x81/0x8e
Apr 17 06:07:44 node1 kernel: [116569.387651] [<ffffffff8113e912>] sys_unlink+0x16/0x18
Apr 17 06:07:44 node1 kernel: [116569.387655] [<ffffffff815701d9>] system_call_fastpath+0x16/0x1b
因此，我们将内核更改为 3.8.8（今天发布），并且每个使用 Apache2 的节点的日志中都出现了相同的错误。但这次，我们没有 INFO 行。
Apr 17 14:39:48 node4 kernel: [ 4074.194315] apache2 D 0000000000000002 0 3042 2144 0x00000000
Apr 17 14:39:48 node4 kernel: [ 4074.194319] ffff880227833d98 0000000000000086 ffff880227832010 0000000000013940
Apr 17 14:39:48 node4 kernel: [ 4074.194323] ffff880227838000 0000000000013940 ffff880227833fd8 0000000000013940
Apr 17 14:39:48 node4 kernel: [ 4074.194326] ffff880227833fd8 0000000000013940 ffff8802365418c0 ffff880227838000
Apr 17 14:39:48 node4 kernel: [ 4074.194329] Call Trace:
Apr 17 14:39:48 node4 kernel: [ 4074.194338] [<ffffffff815681f6>] schedule+0x64/0x66
Apr 17 14:39:48 node4 kernel: [ 4074.194341] [<ffffffff8156843e>] schedule_preempt_disabled+0xe/0x10
Apr 17 14:39:48 node4 kernel: [ 4074.194345] [<ffffffff81567190>] __mutex_lock_common+0x11d/0x18b
Apr 17 14:39:48 node4 kernel: [ 4074.194350] [<ffffffff8113dc27>] ? filename_lookup+0x74/0x84
Apr 17 14:39:48 node4 kernel: [ 4074.194353] [<ffffffff81567219>] __mutex_lock_slowpath+0x1b/0x1d
Apr 17 14:39:48 node4 kernel: [ 4074.194356] [<ffffffff81566fd5>] mutex_lock+0x1b/0x2c
Apr 17 14:39:48 node4 kernel: [ 4074.194360] [<ffffffff8113e76d>] do_unlinkat+0x92/0x231
Apr 17 14:39:48 node4 kernel: [ 4074.194364] [<ffffffff81131d7e>] ? fsnotify_access+0x5d/0x65
Apr 17 14:39:48 node4 kernel: [ 4074.194367] [<ffffffff81132f23>] ? sys_read+0x81/0x8e
Apr 17 14:39:48 node4 kernel: [ 4074.194370] [<ffffffff8113e922>] sys_unlink+0x16/0x18
Apr 17 14:39:48 node4 kernel: [ 4074.194375] [<ffffffff81570259>] system_call_fastpath+0x16/0x1b
我们该如何解决这个问题？你有解决方案吗？
此致，
史蒂芬
编辑更多信息：
同时，我们的 Apache 日志中还有另外一条信息。
[Sun Apr 21 16:54:33 2013] [error] [client 90.48.134.110] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-plate-forme/index2.html
[Sun Apr 21 16:54:37 2013] [error] [client 90.48.134.110] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-plate-forme/index2.html
[Sun Apr 21 16:54:40 2013] [error] [client 84.98.103.74] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:54:43 2013] [error] [client 41.140.52.31] Script timed out before returning headers: examplecom.wsgi, referer: http://www.google.com/url?sa=t&rct=j&q=jeux&source=web&cd=9&ved=0CHwQFjAI&url=http%3A%2F%2Fwww.example.com%2F&ei=nP1zUeGvOujZ0QXs5IGoCA&usg=AFQjCNHUy5HF9h1McY5VwLTLf-8mES4BtQ&bvm=bv.45512109,d.d2k
[Sun Apr 21 16:54:47 2013] [error] [client 109.210.26.71] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/liquid-measure.html
[Sun Apr 21 16:54:52 2013] [error] [client 86.202.162.244] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-strategie/index2.html
[Sun Apr 21 16:54:55 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index31.html
[Sun Apr 21 16:55:03 2013] [error] [client 196.217.219.247] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:04 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index31.html
[Sun Apr 21 16:55:07 2013] [error] [client 89.82.161.71] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:55:09 2013] [error] [client 90.48.134.110] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-plate-forme/index5.html
[Sun Apr 21 16:55:10 2013] [error] [client 80.9.135.15] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-simulation/index22.html
[Sun Apr 21 16:55:11 2013] [error] [client 5.49.161.243] Script timed out before returning headers: examplecom.wsgi, referer: https://www.google.fr/
[Sun Apr 21 16:55:12 2013] [error] [client 188.44.65.194] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:55:16 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index33.html
[Sun Apr 21 16:55:18 2013] [error] [client 109.128.202.223] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/sports-heads-basketball.html
[Sun Apr 21 16:55:26 2013] [error] [client 66.249.73.147] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:27 2013] [error] [client 88.123.238.16] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:30 2013] [error] [client 89.82.161.71] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:55:31 2013] [error] [client 89.82.161.71] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-action/index1.html
[Sun Apr 21 16:55:35 2013] [error] [client 84.98.103.74] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:38 2013] [error] [client 173.199.120.51] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:40 2013] [error] [client 31.38.95.42] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-aventure/index12.html
[Sun Apr 21 16:55:41 2013] [error] [client 78.248.174.131] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:46 2013] [error] [client 78.223.64.116] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:55:49 2013] [error] [client 173.176.47.26] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-cine-tv/index1.html
[Sun Apr 21 16:55:50 2013] [error] [client 82.249.237.18] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:51 2013] [error] [client 23.20.240.42] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:55:52 2013] [error] [client 173.176.47.26] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-cine-tv/index1.html
[Sun Apr 21 16:55:53 2013] [error] [client 88.123.238.16] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:55:53 2013] [error] [client 86.202.162.244] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-strategie/index6.html
[Sun Apr 21 16:55:59 2013] [error] [client 41.200.118.149] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-aventure/index1.html
[Sun Apr 21 16:56:01 2013] [error] [client 78.248.174.131] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:05 2013] [error] [client 90.19.120.106] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:56:06 2013] [error] [client 91.178.96.209] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:56:08 2013] [error] [client 41.140.52.31] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:56:10 2013] [error] [client 90.48.134.110] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-plate-forme/index14.html
[Sun Apr 21 16:56:11 2013] [error] [client 78.248.174.131] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:19 2013] [error] [client 173.199.120.51] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:19 2013] [error] [client 2.12.210.112] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/billiard-blitz-hustle.html
[Sun Apr 21 16:56:21 2013] [error] [client 157.55.33.24] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:23 2013] [error] [client 91.178.96.209] Script timed out before returning headers: examplecom.wsgi, referer: http://www.google.be/search?hl=fr-BE&source=hp&q=jeux&gbv=2&rlz=1W1SKPB_fr&oq=j&gs_l=heirloom-hp.1.0.0l10.2704.2704.0.4782.1.1.0.0.0.0.125.125.0j1.1.0...0.0...1ac.1.IfSicVdYv6I
[Sun Apr 21 16:56:24 2013] [error] [client 90.19.120.106] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/bubble-shooter.html
[Sun Apr 21 16:56:26 2013] [error] [client 86.70.179.202] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-aventure/index3.html
[Sun Apr 21 16:56:27 2013] [error] [client 173.176.47.26] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-puzzles/index1.html
[Sun Apr 21 16:56:28 2013] [error] [client 41.140.52.31] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:29 2013] [error] [client 78.223.64.116] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/historique/
[Sun Apr 21 16:56:34 2013] [error] [client 91.178.96.209] Script timed out before returning headers: examplecom.wsgi, referer: http://www.google.be/search?hl=fr-BE&source=hp&q=jeux&gbv=2&rlz=1W1SKPB_fr&oq=j&gs_l=heirloom-hp.1.0.0l10.2704.2704.0.4782.1.1.0.0.0.0.125.125.0j1.1.0...0.0...1ac.1.IfSicVdYv6I
[Sun Apr 21 16:56:36 2013] [error] [client 105.137.9.237] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/papas-hot-doggeria.html
[Sun Apr 21 16:56:41 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index40.html
[Sun Apr 21 16:56:42 2013] [error] [client 41.224.155.145] Script timed out before returning headers: examplecom.wsgi, referer: https://www.google.tn/
[Sun Apr 21 16:56:45 2013] [error] [client 41.140.52.31] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:45 2013] [error] [client 184.73.108.145] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:51 2013] [error] [client 171.16.210.1] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux/
[Sun Apr 21 16:56:51 2013] [error] [client 77.206.105.160] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/tu-95.html
[Sun Apr 21 16:56:54 2013] [error] [client 157.55.32.184] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:56:55 2013] [error] [client 171.16.210.1] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux/
[Sun Apr 21 16:56:57 2013] [error] [client 41.224.155.145] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:57:00 2013] [error] [client 86.71.134.240] Script timed out before returning headers: examplecom.wsgi, referer: http://www1.delta-search.com/?q=tankiste+jeux&s=web&as=3&rlz=0&babsrc=HP_ss
[Sun Apr 21 16:57:01 2013] [error] [client 41.143.152.123] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/web-action/
[Sun Apr 21 16:57:04 2013] [error] [client 41.140.52.31] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:07 2013] [error] [client 96.31.66.245] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:10 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index43.html
[Sun Apr 21 16:57:11 2013] [error] [client 41.226.161.210] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:15 2013] [error] [client 66.249.73.147] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:23 2013] [error] [client 92.143.167.234] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:26 2013] [error] [client 77.194.131.243] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-reflexion/index47.html
[Sun Apr 21 16:57:32 2013] [error] [client 41.226.161.210] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:33 2013] [error] [client 82.230.45.233] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:37 2013] [error] [client 84.100.172.245] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-divers/index14.html
[Sun Apr 21 16:57:37 2013] [error] [client 93.6.87.57] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:57:38 2013] [error] [client 178.237.80.156] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-simulation/index6.html
[Sun Apr 21 16:57:38 2013] [error] [client 46.126.133.25] Script timed out before returning headers: examplecom.wsgi, referer: http://www.google.ch/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CG4QFjAH&url=http%3A%2F%2Fwww.example.com%2F&ei=DP5zUcC8IIG44AT21oHoAQ&usg=AFQjCNHUy5HF9h1McY5VwLTLf-8mES4BtQ&bvm=bv.45512109,d.bGE
[Sun Apr 21 16:57:46 2013] [error] [client 79.80.168.112] Script timed out before returning headers: examplecom.wsgi, referer: http://files.example.com/278374/1769/1769.swf?201301111413
[Sun Apr 21 16:57:49 2013] [error] [client 89.158.158.137] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:57:49 2013] [error] [client 41.226.161.210] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:50 2013] [error] [client 41.140.115.198] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:57:53 2013] [error] [client 197.6.124.156] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/tous-les-jeux/index9.html
[Sun Apr 21 16:57:56 2013] [error] [client 41.226.161.210] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:57:58 2013] [error] [client 66.249.73.147] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:01 2013] [error] [client 208.78.85.9] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:04 2013] [error] [client 79.80.168.112] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:58:08 2013] [error] [client 178.154.243.93] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:10 2013] [error] [client 65.55.213.67] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:13 2013] [error] [client 2.0.117.243] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:15 2013] [error] [client 93.6.87.57] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/sports-heads-football-championship.html
[Sun Apr 21 16:58:21 2013] [error] [client 84.100.172.245] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-divers/index9.html
[Sun Apr 21 16:58:21 2013] [error] [client 41.141.31.247] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:58:22 2013] [error] [client 90.46.243.124] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/da-vincis-flying-robots.html
[Sun Apr 21 16:58:22 2013] [error] [client 157.55.33.24] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:23 2013] [error] [client 41.141.192.75] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeux-sport/index1.html
[Sun Apr 21 16:58:25 2013] [error] [client 78.242.116.153] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:58:28 2013] [error] [client 50.16.125.173] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:30 2013] [error] [client 109.128.202.223] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/sports-heads-football-championship.html
[Sun Apr 21 16:58:32 2013] [error] [client 96.23.78.172] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:34 2013] [error] [client 85.169.207.226] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/
[Sun Apr 21 16:58:37 2013] [error] [client 82.123.227.217] Script timed out before returning headers: examplecom.wsgi, referer: http://www.example.com/jeu/liquid-measure-3.html
[Sun Apr 21 16:58:37 2013] [error] [client 197.2.87.84] Script timed out before returning headers: examplecom.wsgi, referer: https://www.google.tn/
[Sun Apr 21 16:58:41 2013] [error] [client 65.55.213.67] Script timed out before returning headers: examplecom.wsgi
[Sun Apr 21 16:58:42 2013] [error] [client 197.27.82.96] Script timed out before returning headers: examplecom.wsgi, referer: https://www.google.tn/
[Sun Apr 21 16:58:47 2013] [error] [client 197.2.105.198] Script timed out before returning headers: examplecom.wsgi, referer: http://www.google.tn/url?sa=t&rct=j&q=jeux&source=web&cd=8&cad=rja&ved=0CGgQFjAH&url=http%3A%2F%2Fwww.example.com%2F&ei=kf5zUYOMMITNswbe24DwAg&usg=AFQjCNHUy5HF9h1McY5VwLTLf-8mES4BtQ&bvm=bv.45512109,d.ZWU
[Sun Apr 21 17:02:00 2013] [error] [client 79.80.168.112] (4)Interrupted system call: mod_wsgi (pid=24177): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 66.249.73.147] (4)Interrupted system call: mod_wsgi (pid=23061): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 81.52.143.33] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 88.186.156.156] (4)Interrupted system call: mod_wsgi (pid=26739): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://search.free.fr/google.pl
[Sun Apr 21 17:02:00 2013] [error] [client 41.97.87.84] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.govome.com/web?hl=dz&q=jeux
[Sun Apr 21 17:02:00 2013] [error] [client 109.29.30.203] (4)Interrupted system call: mod_wsgi (pid=26739): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 173.199.120.51] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 41.140.234.23] (4)Interrupted system call: mod_wsgi (pid=26739): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 86.72.195.6] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-action/index72.html
[Sun Apr 21 17:02:00 2013] [error] [client 41.251.99.18] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-combat/index1.html
[Sun Apr 21 17:02:00 2013] [error] [client 109.12.49.236] (4)Interrupted system call: mod_wsgi (pid=26739): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 41.251.99.18] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-action/index23.html
[Sun Apr 21 17:02:00 2013] [error] [client 81.52.143.30] (4)Interrupted system call: mod_wsgi (pid=26739): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 41.250.167.182] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 83.141.225.0] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-course/index10.html
[Sun Apr 21 17:02:00 2013] [error] [client 88.179.62.177] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 65.55.213.77] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 78.239.240.30] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-action/index2.html
[Sun Apr 21 17:02:00 2013] [error] [client 109.12.49.236] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 81.52.143.31] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 82.145.216.39] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 86.215.16.69] (4)Interrupted system call: mod_wsgi (pid=26380): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 50.16.125.173] (4)Interrupted system call: mod_wsgi (pid=27142): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 82.231.128.20] (4)Interrupted system call: mod_wsgi (pid=27142): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/
[Sun Apr 21 17:02:00 2013] [error] [client 90.48.134.110] (4)Interrupted system call: mod_wsgi (pid=27142): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-plate-forme/index37.html
[Sun Apr 21 17:02:00 2013] [error] [client 65.55.213.67] (4)Interrupted system call: mod_wsgi (pid=27142): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts.
[Sun Apr 21 17:02:00 2013] [error] [client 83.141.225.0] (4)Interrupted system call: mod_wsgi (pid=27142): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.example.com/jeux-course/index10.html
[Sun Apr 21 17:02:05 2013] [error] [client 84.102.194.98] (4)Interrupted system call: mod_wsgi (pid=24922): Unable to connect to WSGI daemon process 'www.example.com' on '/var/run/apache2/wsgi.27156.0.16.sock' after multiple attempts., referer: http://www.google.fr/url?sa=t&rct=j&q=jeux&source=web&cd=10&ved=0CHcQFjAJ&url=http%3A%2F%2Fwww.example.com%2F&ei=kv5zUZruFYyrhAf7goHgBQ&usg=AFQjCNHUy5HF9h1McY5VwLTLf-8mES4BtQ
WSGI（并非总是如此）似乎阻止了 Apache2。今天所有文件都在使用 Ext4 的 NFS 上（之前是 ReiserFS，但没有变化）。但是使用旧内核（2.6.32）时，我们没有遇到这个问题，只有使用新内核（3.8.8）时才会遇到这个问题。如果我们终止被阻止的进程，平均负载将恢复正常状态。我们已将 WSGI 版本更改为最新版本，但结果还是一样。
锁定文件的是 NFS 服务器吗？或者您有其他想法？
答案1
我们从调用跟踪中可以看到，Apache 尝试删除一个文件，但因等待释放锁而挂起。由于文件位于 NFS 服务器上，因此您应该查看 NFS 服务器以及 Web 服务器与 NAS 之间的网络连接。
您可能需要确保的一件事是，您已明确指定在两端使用 NFSv4。它比 NFSv3 更可靠，并且解决了以前困扰 NFS 版本的许多问题。服务器应该如果是 RHEL 6 或更高版本，则已经执行此操作。只需确保您已在客户端的挂载选项中指定使用 NFSv4。（例如，nfs4文件系统类型，或nfs带有挂载选项的文件系统类型nfsvers=4。）
答案2
输出是什么
# cat /proc/sys/vm/dirty_ratio
和
# free -mt
Debian 上的默认值为 10：10% 的内存用于缓存
这是有关将数据缓存到内存的一个已知错误，当脏比率过高时，IO 进程可能需要很长时间（最多 120 秒）才能将缓存的内存刷新到磁盘。如果您有大量内存，可以尝试降低此 dirty_ratio
要更改此值以进行测试：
echo 10 > /proc/sys/vm/dirty_ratio
要永久更改，请将其添加到您的 /etc/sysctl.conf：
vm.dirty_ratio=10
编辑：来自内核文档
Note: dirty_bytes is the counterpart of dirty_ratio. Only one of them may be specified at a time. When one sysctl is written it is immediately taken into account to evaluate the dirty memory limits and the other appears as 0 when read.
您需要找到最佳设置，考虑到您的磁盘性能和内存量
编辑-更多信息
好的，那么尝试增加 apache 的超时时间，默认值为 300 秒：超时指令