Re: Performance problem with php

Hi, are you using the "suhosin" patch for PHP ? I can see the same lstat behaviour with my setups, because of suhosin. But for the 8 tentative of reading, are you sure php deliver only one page here ? Olivier Le 20/06/2010 08:49, Vincenzo D'Amore a écrit :

Hello, to have a performance problem with apache/mod_php5 configuration under heavy load the website becomes too slow. Using strace I found what appears to me a strange behavior The strange behavior I want point out is related to a sequence of tentative httpd/mod_php5 does in order to read an php page. In this particular case apache httpd servers tries 8 times before reach and read the file (if you want I can send the complete strace output) More strange all these tentative seems to be correctly completed because of success (0) return code for each line. Ffor every file should be served by apache httpd, apache httpd tries to lstat all directory in path more times: lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *FIRST TENTATIVE* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *SECOND* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 access("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", R_OK) = 0 *THIRD* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *FOURTH* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *FIFTH* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *SIXTH* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 *SEVENTH (blocked in the middle of path scan)* lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP", {st_mode=S_IFDIR|0755, st_size=13312, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al", {st_mode=S_IFDIR|0755, st_size=80, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps", {st_mode=S_IFDIR|0750, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451", {st_mode=S_IFDIR|0755, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs", {st_mode=S_IFDIR|0755, st_size=2048, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages", {st_mode=S_IFDIR|0777, st_size=1024, ...}) = 0 lstat("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 *EIGHT AND FINALLY READ THE FILE* open("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", O_RDONLY) = 416 fstat(416, {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 open("/usr/local/sitipersonali/sitipersonali08/NSP/wa/al/wall/webspace/siteapps/21451/htdocs/wp-content/languages/zh_CN.php", O_RDONLY) = 417 fstat(417, {st_mode=S_IFREG|0777, st_size=1312, ...}) = 0 mmap(NULL, 1312, PROT_READ, MAP_SHARED, 417, 0) = 0x2b4a96443000

munmap(0x2b4a96443000, 1312)            = 0
close(417)                              = 0

read(416, "<?php\r\n// Make the admin interfa"..., 8192) = 1312

read(416, "", 8192)                     = 0
read(416, "", 8192)                     = 0
close(416)                              = 0

Could anybody explain me why I have this behavior and if it is attributable to a misconfiguration of php? Best regards, Vincenzo