ID: 43864
Comment by: nlgordon at iastate dot edu
Reported By: sq6elt at wp dot pl
Status: Open
Bug Type: Performance problem
Operating System: Linux
PHP Version: 5.2.5
New Comment:
I've seen this same issue, and while I agree that it is excessive
considering the realpath cache. It appears to be a byproduct of using
realpath on pretty much all file accesses for includes.
Theoretically the realpath cache could be extended to cover directories
and the like. I know I would like it, my servers get hit hard because
I'm serving php out of AFS space.
Previous Comments:
------------------------------------------------------------------------
[2008-01-16 08:21:25] sq6elt at wp dot pl
Description:
------------
With a lot of includes, located deep in file system,
there may be a performance impact, because of a lot of
unnecessary lstats.
Why, when there is exactly specified path, any lstats are made.
Simple access is sufficient, or I missed something?
If some of these are required, then do it only once.
I have checked php4, it behaves in the same way.
There is no difference, when i use include, include_once, require,
require_once.
Reproduce code:
---------------
Create a directory tree:
mkdir -p /tmp/a/b/c/d/e/f/g/h/i/j
Two empty php scripts:
echo '<? ?>' > /tmp/a/b/c/d/e/f/g/h/i/j/a.php
echo '<? ?>' > /tmp/a/b/c/d/e/f/g/h/i/j/b.php
and a main script /tmp/t.php
<?
include "/tmp/a/b/c/d/e/f/g/h/i/j/a.php";
include "/tmp/a/b/c/d/e/f/g/h/i/j/b.php";
?>
Actual result:
--------------
Do a strace on t,php
strace /usr/bin/php5 t.php 2>&1 | grep lstat64
And guess what:
lstat64("/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/usr/bin", {st_mode=S_IFDIR|0755, st_size=49152, ...}) = 0
lstat64("/usr/bin/php5", {st_mode=S_IFREG|0755, st_size=5510176, ...})
= 0
lstat64("/etc", {st_mode=S_IFDIR|0755, st_size=8192, ...}) = 0
lstat64("/etc/php5", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/etc/php5/cli", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
lstat64("/etc/php5/cli/php.ini", {st_mode=S_IFREG|0644, st_size=44278,
...}) = 0
lstat64("/tmp", {st_mode=S_IFDIR|S_ISVTX|0777, st_size=8192, ...}) = 0
lstat64("/tmp/t.php", {st_mode=S_IFREG|0644, st_size=94, ...}) = 0
lstat64("/tmp", {st_mode=S_IFDIR|S_ISVTX|0777, st_size=8192, ...}) = 0
lstat64("/tmp/a", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d/e", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
lstat64("/tmp/a/b/c/d/e/f", {st_mode=S_IFDIR|0755, st_size=4096, ...})
= 0
lstat64("/tmp/a/b/c/d/e/f/g", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i/j", {st_mode=S_IFDIR|0755,
st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i/j/a.php", {st_mode=S_IFREG|0644,
st_size=11, ...}) = 0
lstat64("/tmp", {st_mode=S_IFDIR|S_ISVTX|0777, st_size=8192, ...}) = 0
lstat64("/tmp/a", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d/e", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
lstat64("/tmp/a/b/c/d/e/f", {st_mode=S_IFDIR|0755, st_size=4096, ...})
= 0
lstat64("/tmp/a/b/c/d/e/f/g", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i", {st_mode=S_IFDIR|0755, st_size=4096,
...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i/j", {st_mode=S_IFDIR|0755,
st_size=4096, ...}) = 0
lstat64("/tmp/a/b/c/d/e/f/g/h/i/j/b.php", {st_mode=S_IFREG|0644,
st_size=7, ...}) = 0
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Edit this bug report at http://bugs.php.net/?id=43864&edit=1
