首先，我在服务器上安装了 xCache，我在很多服务器上都安装了 xCache，但是在这几天之后，除了 apache 错误日志中出现此错误的空白页面外，您什么也没有：
child pid XXXXX exit signal Segmentation fault
据我所知，这意味着某种内存损坏。
所以我从 php.ini 中删除了 xCache 并安装了 APC。但现在情况更糟了。一小时或更少/更多服务器变得无响应后。我可以在我网站的服务器状态中清楚地看到 W 模式下有很多连接。而且他们没有任何共同点。其中一些来自 Joomla（首页），一些来自 vBulletin（论坛），还有一些来自其他自定义代码。如果我让它更长时间，我将在 Apache 错误日志中出现此错误：
Server reached MaxClients setting, consider raising the MaxClients setting
Apache 处于 mod_php 和 mod_ruid2 模式。
这是挂起时服务器状态的结果：
Server uptime: 52 minutes 57 seconds
Total accesses: 31025 - Total Traffic: 279.0 MB
CPU Usage: u418.14 s64.28 cu0 cs0 - 15.2% CPU load
9.77 requests/sec - 89.9 kB/second - 9.2 kB/request
398 requests currently being processed, 27 idle workers
WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
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WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
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WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
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WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
WWWWWWWWWWWWWWWWWWWWWWWWW.......................................
WW___WW_WW_W_WWW__WWWW_W_.......................................
_W___W___WW_W_W_W_W______.......................................
这是 xCache 的错误日志（很多这些行）：
[Thu Mar 28 09:50:38 2013] [notice] child pid 1607 exit signal Aborted (6)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 09:51:57 2013] [notice] child pid 1643 exit signal Aborted (6)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 09:52:32 2013] [notice] child pid 1724 exit signal Aborted (6)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 09:55:21 2013] [notice] child pid 1672 exit signal Aborted (6)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 09:55:56 2013] [notice] child pid 1471 exit signal Aborted (6)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 09:56:49 2013] [notice] child pid 1753 exit signal Aborted (6)
[Thu Mar 28 09:58:29 2013] [notice] child pid 1810 exit signal Segmentation fault (11)
[Thu Mar 28 09:58:29 2013] [notice] child pid 1877 exit signal Segmentation fault (11)
httpd: /usr/src/xcache-2.0.0/utils.c:589: xc_sandbox_error_cb: Assertion `sandbox != ((void *)0)' failed.
[Thu Mar 28 10:01:34 2013] [notice] child pid 1844 exit signal Segmentation fault (11)
[Thu Mar 28 10:01:34 2013] [notice] child pid 1913 exit signal Aborted (6)
[Thu Mar 28 10:01:34 2013] [notice] child pid 1941 exit signal Segmentation fault (11)
[Thu Mar 28 10:01:36 2013] [notice] child pid 2007 exit signal Segmentation fault (11)
[Thu Mar 28 10:01:37 2013] [notice] child pid 2035 exit signal Segmentation fault (11)
[Thu Mar 28 10:01:37 2013] [notice] child pid 2036 exit signal Segmentation fault (11)
APC 在达到最大客户端之前的错误日志（从一次重启到另一次重启）：
[Thu Mar 28 19:17:10 2013] [notice] Apache/2.2.24 (Unix) mod_ssl/2.2.24 OpenSSL/1.0.0-fips DAV/2 PHP/5.2.17 configured -- resuming normal operations
[Thu Mar 28 19:21:40 2013] [notice] child pid 1356 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:41 2013] [notice] child pid 1520 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:42 2013] [notice] child pid 1330 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:42 2013] [notice] child pid 1518 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:46 2013] [notice] child pid 1967 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:46 2013] [notice] child pid 1968 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:49 2013] [notice] child pid 1939 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:50 2013] [notice] child pid 2034 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:51 2013] [notice] child pid 2062 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:57 2013] [notice] child pid 2091 exit signal Segmentation fault (11)
[Thu Mar 28 19:22:58 2013] [notice] child pid 2090 exit signal Segmentation fault (11)
[Thu Mar 28 19:25:34 2013] [notice] caught SIGTERM, shutting down
[Thu Mar 28 19:25:37 2013] [notice] SSL FIPS mode disabled
[Thu Mar 28 19:25:37 2013] [warn] RSA server certificate CommonName (CN) `localhost' does NOT match server name!?
[Thu Mar 28 19:25:37 2013] [warn] Init: Name-based SSL virtual hosts only work for clients with TLS server name indication support (RFC 4366)
[Thu Mar 28 19:25:37 2013] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Thu Mar 28 19:25:38 2013] [notice] SSL FIPS mode disabled
[Thu Mar 28 19:25:38 2013] [warn] RSA server certificate CommonName (CN) `localhost' does NOT match server name!?
[Thu Mar 28 19:25:38 2013] [warn] Init: Name-based SSL virtual hosts only work for clients with TLS server name indication support (RFC 4366)
[Thu Mar 28 19:25:38 2013] [notice] Apache/2.2.24 (Unix) mod_ssl/2.2.24 OpenSSL/1.0.0-fips DAV/2 PHP/5.2.17 configured -- resuming normal operations
来自 PHP 信息的一点点：
System Linux xxx.xxxxx.com 2.6.32-358.0.1.el6.x86_64 #1 SMP Wed Feb 27 06:06:45 UTC 2013 x86_64
Build Date Mar 17 2013 12:55:14
Configure Command './configure' '--with-apxs2' '--with-curl=/usr/local/lib' '--with-gd' '--with-ttf' '--with-gettext' '--with-jpeg-dir=/usr/local/lib' '--with-freetype-dir=/usr/local/lib' '--with-kerberos' '--with-openssl' '--with-mcrypt' '--with-mhash' '--with-mysql=/usr' '--with-mysqli=/usr/bin/mysql_config' '--with-pdo-mysql=/usr' '--with-pcre-regex=/usr/local' '--with-pear' '--with-png-dir=/usr/local/lib' '--with-xsl' '--with-zlib' '--with-zlib-dir=/usr/local/lib' '--with-iconv=/usr/local' '--enable-bcmath' '--enable-calendar' '--enable-exif' '--enable-ftp' '--enable-gd-native-ttf' '--enable-magic-quotes' '--enable-safe-mode' '--enable-soap' '--enable-sockets' '--enable-mbstring' '--enable-zip' '--enable-wddx'
Server API Apache 2.0 Handler
Virtual Directory Support enabled
Configuration File (php.ini) Path /usr/local/lib
Loaded Configuration File /usr/local/lib/php.ini
Scan this dir for additional .ini files (none)
additional .ini files parsed (none)
PHP API 20041225
PHP Extension 20060613
Zend Extension 220060519
Debug Build no
Thread Safety enabled
Zend Memory Manager enabled
IPv6 Support enabled
Registered PHP Streams https, ftps, compress.zlib, php, file, data, http, ftp, zip
Registered Stream Socket Transports tcp, udp, unix, udg, ssl, sslv3, sslv2, tls
Registered Stream Filters zlib.*, convert.iconv.*, string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed
APC 设置：
enabled
Version 3.1.13
APC Debugging Disabled
MMAP Support Enabled
MMAP File Mask no value
Locking type pthread read/write Locks
Serialization Support php
Revision $Revision: 327136 $
Build Date Mar 28 2013 12:40:18
php -v:
PHP 5.2.17 (cli) (built: Mar 17 2013 12:55:24)
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2010 Zend Technologies
httpd -V:
Server version: Apache/2.2.24 (Unix)
Server built: Mar 10 2013 09:18:00
Server's Module Magic Number: 20051115:31
Server loaded: APR 1.4.6, APR-Util 1.4.1
Compiled using: APR 1.4.6, APR-Util 1.4.1
Architecture: 64-bit
Server MPM: Worker
threaded: yes (fixed thread count)
forked: yes (variable process count)
Server compiled with....
-D APACHE_MPM_DIR="server/mpm/worker"
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
-D APR_USE_SYSVSEM_SERIALIZE
-D APR_USE_PTHREAD_SERIALIZE
-D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=128
-D HTTPD_ROOT="/etc/httpd"
-D SUEXEC_BIN="/usr/sbin/suexec"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"
任何的想法？！我会奖励50 :)