Yes, right.

/usr/libexec/php5-cgi/bin/php -v

PHP 5.2.9 (cli) (built: Sep 14 2009 16:52:55)
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2009 Zend Technologies
with the ionCube PHP Loader v3.1.33, Copyright (c) 2002-2007, by ionCube
Ltd.

httpd -V

Server version: Apache/2.2.11 (Unix)
Server built: Jan 8 2009 09:27:22
Server's Module Magic Number: 20051115:21
Server loaded: APR 1.2.7, APR-Util 1.2.7
Compiled using: APR 1.2.7, APR-Util 1.2.7
Architecture: 64-bit
Server MPM: Prefork
threaded: no
forked: yes (variable process count)
Server compiled with....
-D APACHE_MPM_DIR="server/mpm/prefork"
-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_PIDLOG="logs/httpd.pid"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_LOCKFILE="logs/accept.lock"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"

cat /proc/version

Linux version 2.6.18-028stab062.3 (root@rhel5-64-build) (gcc version 4.1.2
20070626 (Red Hat 4.1.2-14)) #1 SMP Thu Mar 26 14:46:38 MSK 2009

On Sun, Jun 20, 2010 at 9:11 AM, Alexey Zakhlestin indeyets@gmail.comwrote:

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.

let's start with the basics.

what version of php is this?
what version of apache (and which mpm) is this?
what OS is this?

--
Alexey Zakhlestin
http://www.milkfarmsoft.com/

--
Vincenzo D'Amore
email: v.damore@gmail.com
msn: freedev@hotmail.com
skype: free.dev
mobile: +39 349 8513251

Hi.

Shouldn't we seeing failed lstats if the include_path would be the problem?
And I thought that the php engine itself tries to cache the fileinfo, to
minimize the lstat calls ( see
http://hu.php.net/manual/en/function.clearstatcache.php )
So I think that we shouldn't see this much duplicate lstat calls.

Tyrael

Hi,

Unfortunately, your web application abused include_path. You can change WP
source code to include PHP files using absolute path

Regards,

Dinh

On Sun, Jun 20, 2010 at 1:49 PM, Vincenzo D'Amore <v.damore@gmail.com

wrote:

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

--
Spica Framework: http://code.google.com/p/spica
http://www.twitter.com/pcdinh
http://groups.google.com/group/phpvietnam

Hi Dinh,

sorry, I don't get why having a wrong include_path configuration inside WP
should have a negative outcome like have 8 tentatives in order to read this
file.

Regards,
Vincenzo

Hi,

Unfortunately, your web application abused include_path. You can change WP
source code to include PHP files using absolute path

Regards,

Dinh

On Sun, Jun 20, 2010 at 1:49 PM, Vincenzo D'Amore v.damore@gmail.comwrote:

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

--
Spica Framework: http://code.google.com/p/spica
http://www.twitter.com/pcdinh
http://groups.google.com/group/phpvietnam

--
Vincenzo D'Amore
email: v.damore@gmail.com
msn: freedev@hotmail.com
skype: free.dev
mobile: +39 349 8513251

Hello Oliver,

looking at php.ini configuration I don't see any suhosin entry, so I think
no.
do you know if there is another way to understand if it is installed?

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

--

--
Vincenzo D'Amore
email: v.damore@gmail.com
msn: freedev@hotmail.com
skype: free.dev
mobile: +39 349 8513251

Is this only useful for 5.2.x and is it only for realpath() or is it for any sort of path lookup and caching? Like resolving include paths and such?

realpath_cache_size = 256k
realpath_cache_ttl = 7200

Thanks Rasmus,

we are using wordpress. Looking at code:

find . -type f -exec grep realpath {} ;

I see a lot of:

if ( function_exists('realpath') )
$path = realpath($path);
if ( function_exists('realpath') )
$path = realpath($path);
if ( function_exists('realpath') )
$path = realpath($path);
if ( realpath($path) == $path )
if ( !is_null($dest_path) and $_dest_path = realpath($dest_path) )

What do you think if I disable such function?

Best regards,
Vincenzo

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

This doesn't look like a PHP misconfiguration. It looks more like an
application-level issue. Do a grep for "realpath" in your application
code. A single call to realpath() would cause that tree of stat calls
you see. Also, you might be overflowing your realpath cache. PHP 5.2
is not using the cache very efficiently. This is fixed in 5.3. But try
increasing your cache ttl and the size as well. eg.

realpath_cache_size = 256k
realpath_cache_ttl = 7200

-Rasmus

--
Vincenzo D'Amore
email: v.damore@gmail.com
msn: freedev@hotmail.com
skype: free.dev
mobile: +39 349 8513251