最近，我发现我的服务器总是高负载，然后我安装Xdebug来跟踪哪个PHP脚本导致高负载。启用模块后，我得到了一个名为trace.2043925204.00879e.xt的文件。我读了这个文件并得到了下面的消息，我的问题是如何检查哪些PHP代码经常执行哪个PHP代码需要很长时间才能执行？
由于
TRACE START [2012-02-08 02:03:30]
0.0002 69336 -> {main}() /srv/www/htdocs/index.php:0
0.0036 324700 -> require_once(/srv/www/htdocs/includes/bootstrap.inc) /srv/www/htdocs/index.php:15
0.0036 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:13
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:18
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:23
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:28
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:35
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:46
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:57
0.0037 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:68
0.0038 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:79
0.0038 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:90
0.0038 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:101
0.0038 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:112
0.0038 324820 -> define() /srv/www/htdocs/includes/bootstrap.inc:123
0.0038 324876 -> define() /srv/www/htdocs/includes/bootstrap.inc:128
0.0038 324876 -> define() /srv/www/htdocs/includes/bootstrap.inc:134
0.0039 324876 -> define() /srv/www/htdocs/includes/bootstrap.inc:139
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:144
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:149
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:155
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:160
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:165
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:171
0.0039 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:176
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:181
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:186
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:192
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:199
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:205
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:210
0.0040 324924 -> define() /srv/www/htdocs/includes/bootstrap.inc:215
0.0041 305356 -> drupal_bootstrap() /srv/www/htdocs/index.php:16
0.0041 305632 -> _drupal_bootstrap() /srv/www/htdocs/includes/bootstrap.inc:1091
0.0041 305892 -> drupal_unset_globals() /srv/www/htdocs/includes/bootstrap.inc:1101
0.0041 305892 -> ini_get() /srv/www/htdocs/includes/bootstrap.inc:342
0.0041 305892 -> timer_start() /srv/www/htdocs/includes/bootstrap.inc:1103
0.0042 306092 -> microtime() /srv/www/htdocs/includes/bootstrap.inc:228
0.0042 306092 -> explode() /srv/www/htdocs/includes/bootstrap.inc:228
0.0042 306660 -> conf_init() /srv/www/htdocs/includes/bootstrap.inc:1105
0.0042 307856 -> strtolower() /srv/www/htdocs/includes/bootstrap.inc:381
0.0043 310772 -> drupal_valid_http_host() /srv/www/htdocs/includes/bootstrap.inc:382