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
