Hello All,
could anybody explain me why if safe_mode or open_basedir are set, realpath
cache is disabled?
Looking at source code main/main.c of 5.2.13 I can see:
1292: /* Disable realpath cache if safe_mode or open_basedir are set */
if (PG(safe_mode) || (PG(open_basedir) && *PG(open_basedir))) {
CWDG(realpath_cache_size_limit) = 0;
}
1769: /* Disable realpath cache if safe_mode or open_basedir are set */
if (PG(safe_mode) || (PG(open_basedir) && *PG(open_basedir))) {
CWDG(realpath_cache_size_limit) = 0;
}
So realpath cache is definitely disabled in case of safe_mode or
open_basedir.
This dramatically reduce performance of PHP Engine and, in a big production
environment, this behavior can bring servers to its knees.
Especially because there is a lack of documentation!
On Fri, Jul 9, 2010 at 7:39 PM, Vincenzo D'Amore <v.dam...@gmail.com> wrote:
> Hello all,
>
> I have already notified to the mailing list a performance problem with
> apache/mod_php5.
>
> Now I have an update and I think this is probably a bug.
> PHP lstat the full path more times before read the file when in apache
> httpd configuration is specified *PHP_ADMIN_VALUE open_basedir *setting.
>
> I have a simple website with only phpinfo.php page and inside we have only
> "<? phpinfo() ?>".
>
> httpd.2.2.15 fresh compiled and PHP 5.2.13.
>
> If is specified *PHP_ADMIN_VALUE open_basedir* in Virtual host
> configuration:
>
> <Directory "/usr/local/myspace/webspace/httpdocs">
> * PHP_ADMIN_VALUE open_basedir
> "/usr/local/myspace/webspace"*
> </Directory>
> <VirtualHost *:80>
> ServerName damorealt.xoom.it
> DocumentRoot "/usr/local/myspace/webspace/httpdocs"
> CustomLog /var/log/httpd/damorealt/access_log combined
> ErrorLog /var/log/httpd/damorealt/error_log
> </VirtualHost >
>
> Calling page http://damorealt.xoom.it/phpinfo.php we can reproduce
> following behavior:
>
> 25933 accept(3, {sa_family=AF_INET, sin_port=htons(47433),
> sin_addr=inet_addr("212.48.14.186")}, [17179869200]) = 15
> 25933 getsockname(15, {sa_family=AF_INET, sin_port=htons(80),
> sin_addr=inet_addr("151.99.197.198")}, [17179869200]) = 0
> 25933 fcntl(15, F_GETFL) = 0x2 (flags O_RDWR)
> 25933 fcntl(15, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 25933 read(15, "GET /phpinfo.php HTTP/1.0\r\nUser-"..., 8000) = 129
> 25933 gettimeofday({1278695388, 52976}, NULL) = 0
> 25933 stat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
> 25933 open("/usr/local/myspace/.htaccess", O_RDONLY) = -1 ENOENT (No such
> file or directory)
> 25933 open("/usr/local/myspace/webspace/.htaccess", O_RDONLY) = -1 ENOENT
> (No such file or directory)
> 25933 open("/usr/local/myspace/webspace/httpdocs/.htaccess", O_RDONLY) = -1
> ENOENT (No such file or directory)
> 25933 open("/usr/local/myspace/webspace/httpdocs/phpinfo.php/.htaccess",
> O_RDONLY) = -1 ENOTDIR (Not a directory)
> 25933 setitimer(ITIMER_PROF, {it_interval={0, 0}, it_value={20, 0}}, NULL)
> = 0
> 25933 rt_sigaction(SIGPROF, {0x2b80442fdd80, [PROF],
> SA_RESTORER|SA_RESTART, 0x3916e302d0}, {SIG_DFL, [], 0}, 8) = 0
> 25933 rt_sigprocmask(SIG_UNBLOCK, [PROF], NULL, 8) = 0
> 25933 getcwd("/"..., 4095) = 2
> 25933 chdir("/usr/local/myspace/webspace/httpdocs") = 0
>
> *water boiling point*
>
> 25933 lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace", {st_mode=S_IFDIR|0755, st_size=4096,
> ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
>
> First check
>
> 25933 lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace", {st_mode=S_IFDIR|0755, st_size=4096,
> ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
>
> Second check
>
> 25933 lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace", {st_mode=S_IFDIR|0755, st_size=4096,
> ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
>
> Third check (incomplete)
>
> 25933 lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace", {st_mode=S_IFDIR|0755, st_size=4096,
> ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 25933 lstat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
>
> Final check and then read the file.
>
> 25933 open("/usr/local/myspace/webspace/httpdocs/phpinfo.php", O_RDONLY) =
> 16
> 25933 fstat(16, {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
> 25933 read(16, "<? phpinfo() ?>\n", 8192) = 16
> 25933 read(16, "", 8192) = 0
> 25933 read(16, "", 8192) = 0
> 25933 close(16) = 0
>
>
> If *PHP_ADMIN_VALUE open_basedir "/usr/local/myspace/webspace" is removed
> * in virtual host configuration we finally have simpliest behavior:
>
> 226235 accept(3, {sa_family=AF_INET, sin_port=htons(59366),
> sin_addr=inet_addr("212.48.14.186")}, [17179869200]) = 15
> 26235 getsockname(15, {sa_family=AF_INET, sin_port=htons(80),
> sin_addr=inet_addr("151.99.197.198")}, [17179869200]) = 0
> 26235 fcntl(15, F_GETFL) = 0x2 (flags O_RDWR)
> 26235 fcntl(15, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 26235 read(15, "GET /phpinfo.php HTTP/1.0\r\nUser-"..., 8000) = 129
> 26235 gettimeofday({1278696735, 988799}, NULL) = 0
> 26235 stat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
> 26235 open("/usr/local/myspace/.htaccess", O_RDONLY) = -1 ENOENT (No such
> file or directory)
> 26235 open("/usr/local/myspace/webspace/.htaccess", O_RDONLY) = -1 ENOENT
> (No such file or directory)
> 26235 open("/usr/local/myspace/webspace/httpdocs/.htaccess", O_RDONLY) = -1
> ENOENT (No such file or directory)
> 26235 open("/usr/local/myspace/webspace/httpdocs/phpinfo.php/.htaccess",
> O_RDONLY) = -1 ENOTDIR (Not a directory)
> 26235 setitimer(ITIMER_PROF, {it_interval={0, 0}, it_value={20, 0}}, NULL)
> = 0
> 26235 rt_sigaction(SIGPROF, {0x2afef587dd80, [PROF],
> SA_RESTORER|SA_RESTART, 0x3916e302d0}, {SIG_DFL, [], 0}, 8) = 0
> 26235 rt_sigprocmask(SIG_UNBLOCK, [PROF], NULL, 8) = 0
> 26235 getcwd("/"..., 4095) = 2
> 26235 chdir("/usr/local/myspace/webspace/httpdocs") = 0
>
> *water boiling point*
>
> 26235 time(NULL) = 1278696735
> 26235 lstat("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 26235 lstat("/usr/local", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
> 26235 lstat("/usr/local/myspace", {st_mode=S_IFDIR|0755, st_size=4096,
> ...}) = 0
> 26235 lstat("/usr/local/myspace/webspace", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 26235 lstat("/usr/local/myspace/webspace/httpdocs", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) = 0
> 26235 lstat("/usr/local/myspace/webspace/httpdocs/phpinfo.php",
> {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
>
> And read the file.
>
> 26235 open("/usr/local/myspace/webspace/httpdocs/phpinfo.php", O_RDONLY) =
> 16
> 26235 fstat(16, {st_mode=S_IFREG|0644, st_size=16, ...}) = 0
> 26235 read(16, "<? phpinfo() ?>\n", 8192) = 16
> 26235 read(16, "", 8192) = 0
> 26235 read(16, "", 8192) = 0
> 26235 close(16) = 0
> 26235 uname({sys="Linux", node="svilpar4", ...}) = 0
> 26235 time(NULL) = 1278696735
> 26235 writev(15, [{"HTTP/1.1 200 OK\r\nDate: Fri, 09 J"..., 173},
> {"<!DOCTYPE html PUBLIC \"-//W3C//D"..., 4109}, {"<table border=\"0\"
> cellpadding=\"3"..., 4101}], 3) = 8383
> 26235 writev(15, [{"<tr><td class=\"e\">highlight.bg</"..., 4105},
> {"sendmail_from</td><td class=\"v\">"..., 4099}], 2) = 8204
> 26235 time(NULL) = 1278696735
> 26235 writev(15, [{" </td></tr>\n<tr><td class=\"e\">HT"..., 4108},
> {"</td><td class=\"v\">1024</td><td "..., 4098}], 2) = 8206
> 26235 writev(15, [{"md2 md4 md5 sha1 sha256 sha384 s"..., 4098}, {"
> </td></tr>\n</table><br />\n<tabl"..., 4106}], 2) = 8204
> 26235 writev(15, [{"session.use_cookies</td><td clas"..., 4104}, {"
> </td><td class=\"v\">enabled </td"..., 4102}], 2) = 8206
> 26235 chdir("/") = 0
> 26235 setitimer(ITIMER_PROF, {it_interval={0, 0}, it_value={0, 0}}, NULL) =
> 0
> 26235 writev(15, [{"\"]</td><td class=\"v\">Keep-Alive<"..., 4206}], 1) =
> 4206
> 26235 write(10, "212.48.14.186 - - [09/Jul/2010:1"..., 116) = 116
> 26235 shutdown(15, 1 /* send */) = 0
> 26235 poll([{fd=15, events=POLLIN}], 1, 2000) = 1 ([{fd=15,
> revents=POLLIN|POLLHUP}])
> 26235 read(15, "", 512) = 0
> 26235 close(15) = 0
> 26235 read(4, 0x7fff615ff5eb, 1) = -1 EAGAIN (Resource temporarily
> unavailable)
> 26235 accept(3,
>
> Note that this behavior also happens when safemode is ON.
>
> Can somebody explain me why PHP have such behavior?
>
> Best regards,
> Vincenzo
>
--
Vincenzo D'Amore
email: v.dam...@gmail.com
msn: free...@hotmail.com
skype: free.dev
mobile: +39 349 8513251
