网站访问量非常小，之前有段时间是每周末结束回来就会出现 504错误，重启fastcgi 就OK，后来频率变得越来越高，从一周变成一天，到半天，但是中间代码没有什么大的变动，感觉很奇怪。
在服务器上运行 netstat 命令得到的结果如下 ：
不知道大家遇到这类问题是一般是怎么去调试呢？还有Active UNIX domain sockets (w/o servers)
这个下面这对东西有没有问题？
$ netstat
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 localhost:9099 localhost:45614 SYN_RECV
tcp 0 0 localhost:9099 localhost:45615 SYN_RECV
tcp 0 0 localhost:9099 localhost:45613 SYN_RECV
tcp 0 0 localhost:9099 localhost:45612 SYN_RECV
tcp 0 0 localhost:9099 localhost:45616 SYN_RECV
tcp 513 0 localhost:9099 localhost:44474 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44375 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44423 CLOSE_WAIT
tcp 457 0 localhost:9099 localhost:44365 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44517 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44346 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44378 CLOSE_WAIT
tcp 0 521 localhost:45614 localhost:9099 FIN_WAIT1
tcp 505 0 localhost:9099 localhost:44399 CLOSE_WAIT
tcp 0 561 localhost:45615 localhost:9099 FIN_WAIT1
tcp 625 0 localhost:9099 localhost:44337 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44402 CLOSE_WAIT
tcp 561 0 localhost:9099 localhost:44425 CLOSE_WAIT
tcp 673 0 localhost:9099 localhost:44409 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44416 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44508 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44433 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44442 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44405 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44341 CLOSE_WAIT
tcp 657 0 localhost:9099 localhost:44503 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44336 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44489 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44382 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44397 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44370 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44521 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44340 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44494 CLOSE_WAIT
tcp 441 0 localhost:9099 localhost:44478 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44391 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44495 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44332 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44473 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44470 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44468 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44424 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44447 CLOSE_WAIT
tcp 473 0 localhost:9099 localhost:44361 CLOSE_WAIT
tcp 473 0 localhost:9099 localhost:44484 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44412 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44383 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44355 CLOSE_WAIT
tcp 473 0 localhost:9099 localhost:44481 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44446 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44394 CLOSE_WAIT
tcp 489 0 localhost:9099 localhost:44324 CLOSE_WAIT
tcp 545 0 localhost:9099 localhost:44400 CLOSE_WAIT
tcp 481 0 localhost:9099 localhost:44487 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44418 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44457 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44438 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44502 CLOSE_WAIT
tcp 681 0 localhost:9099 localhost:44344 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44486 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44323 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44362 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44327 CLOSE_WAIT
tcp 457 0 localhost:9099 localhost:44522 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44513 CLOSE_WAIT
tcp 569 0 localhost:9099 localhost:44458 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44437 CLOSE_WAIT
tcp 569 0 localhost:9099 localhost:pmcd CLOSE_WAIT
tcp 489 0 localhost:9099 localhost:44462 CLOSE_WAIT
tcp 569 0 localhost:9099 localhost:44328 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44485 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44430 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44434 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44453 CLOSE_WAIT
tcp 481 0 localhost:9099 localhost:44519 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44480 CLOSE_WAIT
tcp 681 0 localhost:9099 localhost:44401 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44334 CLOSE_WAIT
tcp 481 0 localhost:9099 localhost:44482 CLOSE_WAIT
tcp 673 0 localhost:9099 localhost:44455 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44428 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44518 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:pmcdproxy CLOSE_WAIT
tcp 489 0 localhost:9099 localhost:44498 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44467 CLOSE_WAIT
tcp 433 0 localhost:9099 localhost:44477 CLOSE_WAIT
tcp 457 0 localhost:9099 localhost:44363 CLOSE_WAIT
tcp 681 0 localhost:9099 localhost:44451 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44385 CLOSE_WAIT
tcp 0 0 xx.xx.xx.xx:http crawl-66-249-76-235.g:36350 ESTABLISHED
tcp 473 0 localhost:9099 localhost:44358 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44444 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44353 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44325 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44377 CLOSE_WAIT
tcp 673 0 localhost:9099 localhost:44501 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44499 CLOSE_WAIT
tcp 0 0 xx.xx.xx.xx:ssh 114.248.169.70:56609 ESTABLISHED
tcp 689 0 localhost:9099 localhost:44516 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44364 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44359 CLOSE_WAIT
tcp 0 0 xx.xx.xx.xx:ssh 114.248.169.70:57441 ESTABLISHED
tcp 521 0 localhost:9099 localhost:44415 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44395 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44411 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44360 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44413 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44406 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44356 CLOSE_WAIT
tcp 905 0 localhost:9099 localhost:44440 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44465 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44510 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44347 CLOSE_WAIT
tcp 521 0 localhost:9099 localhost:44372 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44366 CLOSE_WAIT
tcp 489 0 localhost:9099 localhost:44338 CLOSE_WAIT
tcp 465 0 localhost:9099 localhost:44483 CLOSE_WAIT
tcp 905 0 localhost:9099 localhost:44436 CLOSE_WAIT
tcp 449 0 localhost:9099 localhost:44379 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44393 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44403 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44371 CLOSE_WAIT
tcp 513 0 localhost:9099 localhost:44374 CLOSE_WAIT
tcp 505 0 localhost:9099 localhost:44333 CLOSE_WAIT
tcp 625 0 localhost:9099 localhost:44461 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44449 CLOSE_WAIT
tcp 681 0 localhost:9099 localhost:44497 CLOSE_WAIT
tcp 905 0 localhost:9099 localhost:44476 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44491 CLOSE_WAIT
tcp 0 520 localhost:45616 localhost:9099 ESTABLISHED
tcp 513 0 localhost:9099 localhost:44504 CLOSE_WAIT
tcp 689 0 localhost:9099 localhost:44384 CLOSE_WAIT
tcp 441 0 localhost:9099 localhost:44512 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44479 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44427 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44414 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44432 CLOSE_WAIT
tcp 497 0 localhost:9099 localhost:44463 CLOSE_WAIT
tcp 673 0 localhost:9099 localhost:44352 CLOSE_WAIT
tcp 633 0 localhost:9099 localhost:44396 CLOSE_WAIT
tcp 0 4860 xx.xx.xx.xx:ssh 123.120.30.5:38913 ESTABLISHED
Active UNIX domain sockets (w/o servers)
Proto RefCnt Flags Type State I-Node Path
unix 2 [ ] DGRAM 609897 @/org/kernel/udev/udevd
unix 2 [ ] DGRAM 16202 @/org/freedesktop/hal/udev_event
unix 16 [ ] DGRAM 628931 /dev/log
unix 3 [ ] STREAM CONNECTED 31371466
unix 3 [ ] STREAM CONNECTED 31371465
unix 2 [ ] DGRAM 31371462
unix 2 [ ] DGRAM 31368809
unix 2 [ ] UNKNOWN DISCONNECTING 0
unix 2 [ ] STREAM 31356911
unix 2 [ ] DGRAM 31356908
unix 2 [ ] UNKNOWN DISCONNECTING 0
unix 2 [ ] STREAM 31342249
unix 2 [ ] DGRAM 31342246
unix 2 [ ] UNKNOWN DISCONNECTING 0
unix 2 [ ] STREAM 31318762
unix 2 [ ] DGRAM 31318761
unix 2 [ ] UNKNOWN DISCONNECTING 0
unix 2 [ ] STREAM 31263304
unix 2 [ ] DGRAM 31263300
unix 3 [ ] STREAM CONNECTED 31253401
unix 3 [ ] STREAM CONNECTED 31253400
unix 3 [ ] STREAM CONNECTED 31253399
unix 3 [ ] STREAM CONNECTED 31253398
unix 3 [ ] STREAM CONNECTED 31253397
unix 3 [ ] STREAM CONNECTED 31253396
unix 3 [ ] STREAM CONNECTED 31253395
unix 3 [ ] STREAM CONNECTED 31253394
unix 2 [ ] STREAM CONNECTED 31253390
unix 3 [ ] STREAM CONNECTED 31253287
unix 3 [ ] STREAM CONNECTED 31253286
unix 2 [ ] DGRAM 31253283
unix 3 [ ] STREAM CONNECTED 31247947
unix 3 [ ] STREAM CONNECTED 31247946
unix 3 [ ] STREAM CONNECTED 31247945
unix 3 [ ] STREAM CONNECTED 31247944
unix 3 [ ] STREAM CONNECTED 31247943
unix 3 [ ] STREAM CONNECTED 31247942
unix 3 [ ] STREAM CONNECTED 31247941
unix 3 [ ] STREAM CONNECTED 31247940
unix 2 [ ] STREAM CONNECTED 31247936
unix 3 [ ] STREAM CONNECTED 31178429
unix 3 [ ] STREAM CONNECTED 31178428
unix 3 [ ] STREAM CONNECTED 31171939
unix 3 [ ] STREAM CONNECTED 31171938
unix 2 [ ] DGRAM 31171935
unix 3 [ ] STREAM CONNECTED 27227510
unix 3 [ ] STREAM CONNECTED 27227509
unix 3 [ ] STREAM CONNECTED 27227508
unix 3 [ ] STREAM CONNECTED 27227507
unix 3 [ ] STREAM CONNECTED 27227506
unix 3 [ ] STREAM CONNECTED 27227505
unix 3 [ ] STREAM CONNECTED 27227504
unix 3 [ ] STREAM CONNECTED 27227503
unix 3 [ ] STREAM CONNECTED 27227502
unix 3 [ ] STREAM CONNECTED 27227501
unix 3 [ ] STREAM CONNECTED 27227500
unix 3 [ ] STREAM CONNECTED 27227499
unix 3 [ ] STREAM CONNECTED 27227498
unix 3 [ ] STREAM CONNECTED 27227497
unix 3 [ ] STREAM CONNECTED 27227496
unix 3 [ ] STREAM CONNECTED 27227495
unix 3 [ ] STREAM CONNECTED 27227494
unix 3 [ ] STREAM CONNECTED 27227493
unix 3 [ ] STREAM CONNECTED 27227492
unix 3 [ ] STREAM CONNECTED 27227491
unix 2 [ ] STREAM CONNECTED 27227487
unix 2 [ ] DGRAM 24840891
unix 2 [ ] DGRAM 24840814
unix 2 [ ] DGRAM 24834624
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 2 [ ] STREAM CONNECTING 0 /var/run/abrt/abrt.socket
unix 3 [ ] STREAM CONNECTED 1131884
unix 3 [ ] STREAM CONNECTED 1131883
unix 3 [ ] STREAM CONNECTED 1131882
unix 3 [ ] STREAM CONNECTED 1131881
unix 3 [ ] STREAM CONNECTED 1131880
unix 3 [ ] STREAM CONNECTED 1131879
unix 3 [ ] STREAM CONNECTED 1131878
unix 3 [ ] STREAM CONNECTED 1131877
unix 2 [ ] STREAM CONNECTED 1131873
unix 2 [ ] DGRAM 1088807
unix 2 [ ] DGRAM 631192
unix 2 [ ] DGRAM 629682
unix 2 [ ] DGRAM 625326
unix 2 [ ] DGRAM 616785
unix 3 [ ] DGRAM 609927
unix 3 [ ] DGRAM 609926
unix 3 [ ] STREAM CONNECTED 17181
unix 3 [ ] STREAM CONNECTED 17180
unix 3 [ ] STREAM CONNECTED 17177
unix 3 [ ] STREAM CONNECTED 17176
unix 3 [ ] STREAM CONNECTED 17173
unix 3 [ ] STREAM CONNECTED 17172
unix 3 [ ] STREAM CONNECTED 17168
unix 3 [ ] STREAM CONNECTED 17167
unix 3 [ ] STREAM CONNECTED 17164
unix 3 [ ] STREAM CONNECTED 17163
unix 3 [ ] STREAM CONNECTED 17160
unix 3 [ ] STREAM CONNECTED 17159
unix 3 [ ] STREAM CONNECTED 17155
unix 3 [ ] STREAM CONNECTED 17154
unix 3 [ ] STREAM CONNECTED 17151
unix 3 [ ] STREAM CONNECTED 17150
unix 3 [ ] STREAM CONNECTED 17147
unix 3 [ ] STREAM CONNECTED 17145
unix 3 [ ] STREAM CONNECTED 17142
unix 3 [ ] STREAM CONNECTED 17141
unix 3 [ ] STREAM CONNECTED 17138
unix 3 [ ] STREAM CONNECTED 17137
unix 3 [ ] STREAM CONNECTED 17134
unix 3 [ ] STREAM CONNECTED 17133
unix 3 [ ] STREAM CONNECTED 17130
unix 3 [ ] STREAM CONNECTED 17129
unix 3 [ ] STREAM CONNECTED 17126
unix 3 [ ] STREAM CONNECTED 17125
unix 3 [ ] STREAM CONNECTED 17122
unix 3 [ ] STREAM CONNECTED 17121
unix 3 [ ] STREAM CONNECTED 17118
unix 3 [ ] STREAM CONNECTED 17117
unix 3 [ ] STREAM CONNECTED 17114
unix 3 [ ] STREAM CONNECTED 17113
unix 3 [ ] STREAM CONNECTED 17110
unix 3 [ ] STREAM CONNECTED 17109
unix 3 [ ] STREAM CONNECTED 17106
unix 3 [ ] STREAM CONNECTED 17105
unix 3 [ ] STREAM CONNECTED 17102
unix 3 [ ] STREAM CONNECTED 17101
unix 3 [ ] STREAM CONNECTED 17098
unix 3 [ ] STREAM CONNECTED 17097
unix 3 [ ] STREAM CONNECTED 17094
unix 3 [ ] STREAM CONNECTED 17093
unix 3 [ ] STREAM CONNECTED 17090
unix 3 [ ] STREAM CONNECTED 17089
unix 3 [ ] STREAM CONNECTED 17087
unix 3 [ ] STREAM CONNECTED 17086
unix 2 [ ] DGRAM 17036
unix 3 [ ] STREAM CONNECTED 16423 /var/run/acpid.socket
unix 3 [ ] STREAM CONNECTED 16422
unix 3 [ ] STREAM CONNECTED 16417 @/var/run/hald/dbus-PLTrnFGoYa
unix 3 [ ] STREAM CONNECTED 16416
unix 3 [ ] STREAM CONNECTED 16378 @/var/run/hald/dbus-PLTrnFGoYa
unix 3 [ ] STREAM CONNECTED 16297
unix 3 [ ] STREAM CONNECTED 16197 @/var/run/hald/dbus-YyLOb5j6TM
unix 3 [ ] STREAM CONNECTED 16196
unix 3 [ ] STREAM CONNECTED 16175 /var/run/dbus/system_bus_socket
unix 3 [ ] STREAM CONNECTED 16174
unix 2 [ ] DGRAM 16141
unix 3 [ ] STREAM CONNECTED 16021 /var/run/dbus/system_bus_socket
unix 3 [ ] STREAM CONNECTED 16020
unix 3 [ ] STREAM CONNECTED 16015
unix 3 [ ] STREAM CONNECTED 16014
unix 3 [ ] STREAM CONNECTED 13036
unix 3 [ ] STREAM CONNECTED 13035
出现504错误的话。主要主要后面实体服务请求时间估计是要比较大的时间。其实这个可以在你的nginx中加入几个参数试一下。使用fastcgi或是反向代理proxy加入超时时间。还有就是client_header_timeout，client_body_timeout，send_timeout.
正文完